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Sample records for syringae hopz1a type

  1. Auto-acetylation on K289 is not essential for HopZ1a-mediated plant defense suppression

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    Jose Sebastian Rufian

    2015-07-01

    Full Text Available The Pseudomonas syringae type III-secreted effector HopZ1a is a member of the HopZ / YopJ superfamily of effectors that triggers immunity in Arabidopsis. We have previously shown that HopZ1a suppresses both local (effector-triggered immunity, ETI and systemic immunity (systemic acquired resistance, SAR triggered by the heterologous effector AvrRpt2. HopZ1a has been shown to possess acetyltransferase activity, and this activity is essential to trigger immunity in Arabidopsis. HopZ1a acetyltransferase activity has been reported to require the auto-acetylation of the effector on a specific lysine (K289 residue. In this paper we analyze the relevance of autoacetylation of lysine residue 289 in HopZ1a ability to suppress plant defenses, and on the light of the results obtained, we also revise its relevance for HopZ1a avirulence activity. Our results indicate that, while the HopZ1aK289R mutant is impaired to some degree in its virulence and avirulence activities, is by no means phenotypically equivalent to the catalytically inactive HopZ1aC216A, since it is still able to trigger a defense response that induces detectable macroscopic HR and effectively protects Arabidopsis from infection, reducing growth of P. syringae within the plant. We also present evidence that the HopZ1aK289R mutant still displays virulence activities, partially suppressing both ETI and SAR.

  2. Auto-acetylation on K289 is not essential for HopZ1a-mediated plant defense suppression.

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    Rufián, José S; Lucía, Ainhoa; Macho, Alberto P; Orozco-Navarrete, Begoña; Arroyo-Mateos, Manuel; Bejarano, Eduardo R; Beuzón, Carmen R; Ruiz-Albert, Javier

    2015-01-01

    The Pseudomonas syringae type III-secreted effector HopZ1a is a member of the HopZ/YopJ superfamily of effectors that triggers immunity in Arabidopsis. We have previously shown that HopZ1a suppresses both local [effector-triggered immunity (ETI)] and systemic immunity [systemic acquired resistance (SAR)] triggered by the heterologous effector AvrRpt2. HopZ1a has been shown to possess acetyltransferase activity, and this activity is essential to trigger immunity in Arabidopsis. HopZ1a acetyltransferase activity has been reported to require the auto-acetylation of the effector on a specific lysine (K289) residue. In this paper we analyze the relevance of autoacetylation of lysine residue 289 in HopZ1a ability to suppress plant defenses, and on the light of the results obtained, we also revise its relevance for HopZ1a avirulence activity. Our results indicate that, while the HopZ1a(K289R) mutant is impaired to some degree in its virulence and avirulence activities, is by no means phenotypically equivalent to the catalytically inactive HopZ1a(C216A), since it is still able to trigger a defense response that induces detectable macroscopic HR and effectively protects Arabidopsis from infection, reducing growth of P. syringae within the plant. We also present evidence that the HopZ1a(K289R) mutant still displays virulence activities, partially suppressing both ETI and SAR.

  3. Immunomodulation by the Pseudomonas syringae HopZ type III effector family in Arabidopsis.

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    Jennifer D Lewis

    Full Text Available Pseudomonas syringae employs a type III secretion system to inject 20-30 different type III effector (T3SE proteins into plant host cells. A major role of T3SEs is to suppress plant immune responses and promote bacterial infection. The YopJ/HopZ acetyltransferases are a superfamily of T3SEs found in both plant and animal pathogenic bacteria. In P. syringae, this superfamily includes the evolutionarily diverse HopZ1, HopZ2 and HopZ3 alleles. To investigate the roles of the HopZ family in immunomodulation, we generated dexamethasone-inducible T3SE transgenic lines of Arabidopsis for HopZ family members and characterized them for immune suppression phenotypes. We show that all of the HopZ family members can actively suppress various facets of Arabidopsis immunity in a catalytic residue-dependent manner. HopZ family members can differentially suppress the activation of mitogen-activated protein (MAP kinase cascades or the production of reactive oxygen species, whereas all members can promote the growth of non-virulent P. syringae. Localization studies show that four of the HopZ family members containing predicted myristoylation sites are localized to the vicinity of the plasma membrane while HopZ3 which lacks the myristoylation site is at least partially nuclear localized, suggesting diversification of immunosuppressive mechanisms. Overall, we demonstrate that despite significant evolutionary diversification, all HopZ family members can suppress immunity in Arabidopsis.

  4. The Pseudomonas syringae type III effector HopF2 suppresses Arabidopsis stomatal immunity.

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    Brenden Hurley

    Full Text Available Pseudomonas syringae subverts plant immune signalling through injection of type III secreted effectors (T3SE into host cells. The T3SE HopF2 can disable Arabidopsis immunity through Its ADP-ribosyltransferase activity. Proteomic analysis of HopF2 interacting proteins identified a protein complex containing ATPases required for regulating stomatal aperture, suggesting HopF2 may manipulate stomatal immunity. Here we report HopF2 can inhibit stomatal immunity independent of its ADP-ribosyltransferase activity. Transgenic expression of HopF2 in Arabidopsis inhibits stomatal closing in response to P. syringae and increases the virulence of surface inoculated P. syringae. Further, transgenic expression of HopF2 inhibits flg22 induced reactive oxygen species production. Intriguingly, ADP-ribosyltransferase activity is dispensable for inhibiting stomatal immunity and flg22 induced reactive oxygen species. Together, this implies HopF2 may be a bifunctional T3SE with ADP-ribosyltransferase activity required for inhibiting apoplastic immunity and an independent function required to inhibit stomatal immunity.

  5. Plant flavonoids target Pseudomonas syringae pv. tomato DC3000 flagella and type III secretion system.

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    Vargas, Paola; Farias, Gabriela A; Nogales, Joaquina; Prada, Harold; Carvajal, Vivian; Barón, Matilde; Rivilla, Rafael; Martín, Marta; Olmedilla, Adela; Gallegos, María-Trinidad

    2013-12-01

    Flavonoids are among the most abundant plant secondary metabolites involved in plant protection against pathogens, but micro-organisms have developed resistance mechanisms to those compounds. We previously demonstrated that the MexAB-OprM efflux pump mediates resistance of Pseudomonas syringae pv. tomato (Pto) DC3000 to flavonoids, facilitating its survival and the colonization of the host. Here, we have shown that tomato plants respond to Pto infection producing flavonoids and other phenolic compounds. The effects of flavonoids on key traits of this model plant-pathogen bacterium have also been investigated observing that they reduce Pto swimming and swarming because of the loss of flagella, and also inhibited the expression and assembly of a functional type III secretion system. Those effects were more severe in a mutant lacking the MexAB-OprM pump. Our results suggest that flavonoids inhibit the function of the GacS/GacA two-component system, causing a depletion of rsmY RNA, therefore affecting the synthesis of two important virulence factors in Pto DC3000, flagella and the type III secretion system. These data provide new insights into the flavonoid role in the molecular dialog between host and pathogen. © 2013 John Wiley & Sons Ltd and Society for Applied Microbiology.

  6. Phylogenetic analysis of a gene cluster encoding an additional, rhizobial-like type III secretion system that is narrowly distributed among Pseudomonas syringae strains

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    2012-01-01

    Background The central role of Type III secretion systems (T3SS) in bacteria-plant interactions is well established, yet unexpected findings are being uncovered through bacterial genome sequencing. Some Pseudomonas syringae strains possess an uncharacterized cluster of genes encoding putative components of a second T3SS (T3SS-2) in addition to the well characterized Hrc1 T3SS which is associated with disease lesions in host plants and with the triggering of hypersensitive response in non-host plants. The aim of this study is to perform an in silico analysis of T3SS-2, and to compare it with other known T3SSs. Results Based on phylogenetic analysis and gene organization comparisons, the T3SS-2 cluster of the P. syringae pv. phaseolicola strain is grouped with a second T3SS found in the pNGR234b plasmid of Rhizobium sp. These additional T3SS gene clusters define a subgroup within the Rhizobium T3SS family. Although, T3SS-2 is not distributed as widely as the Hrc1 T3SS in P. syringae strains, it was found to be constitutively expressed in P. syringae pv phaseolicola through RT-PCR experiments. Conclusions The relatedness of the P. syringae T3SS-2 to a second T3SS from the pNGR234b plasmid of Rhizobium sp., member of subgroup II of the rhizobial T3SS family, indicates common ancestry and/or possible horizontal transfer events between these species. Functional analysis and genome sequencing of more rhizobia and P. syringae pathovars may shed light into why these bacteria maintain a second T3SS gene cluster in their genome. PMID:22937899

  7. Virulence determinants of Pseudomonas syringae strains isolated from grasses in the context of a small type III effector repertoire

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    Dudnik, Alexey; Dudler, Robert

    2014-01-01

    derivative that inhibits the eukaryotic proteasome. In strains colonizing dicotyledonous plants, the compound was demonstrated to suppress the salicylic-acid-dependent defense pathway. Here, we analyze virulence factors of three strains colonizing wheat (Triticum aestivum): P. syringae pathovar syringae (Psy...

  8. Extensive remodeling of the Pseudomonas syringae pv. avellanae type III secretome associated with two independent host shifts onto hazelnut

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    O’Brien Heath E

    2012-07-01

    Full Text Available Abstract Background Hazelnut (Corylus avellana decline disease in Greece and Italy is caused by the convergent evolution of two distantly related lineages of Pseudomonas syringae pv. avellanae (Pav. We sequenced the genomes of three Pav isolates to determine if their convergent virulence phenotype had a common genetic basis due to either genetic exchange between lineages or parallel evolution. Results We found little evidence for horizontal transfer (recombination of genes between Pav lineages, but two large genomic islands (GIs have been recently acquired by one of the lineages. Evolutionary analyses of the genes encoding type III secreted effectors (T3SEs that are translocated into host cells and are important for both suppressing and eliciting defense responses show that the two Pav lineages have dramatically different T3SE profiles, with only two shared putatively functional T3SEs. One Pav lineage has undergone unprecedented secretome remodeling, including the acquisition of eleven new T3SEs and the loss or pseudogenization of 15, including five of the six core T3SE families that are present in the other Pav lineage. Molecular dating indicates that divergence within both of the Pav lineages predates their observation in the field. This suggest that both Pav lineages have been cryptically infecting hazelnut trees or wild relatives for many years, and that the emergence of hazelnut decline in the 1970s may have been due to changes in agricultural practice. Conclusions These data show that divergent lineages of P. syringae can converge on identical disease etiology on the same host plant using different virulence mechanisms and that dramatic shifts in the arsenal of T3SEs can accompany disease emergence.

  9. Extensive remodeling of the Pseudomonas syringae pv. avellanae type III secretome associated with two independent host shifts onto hazelnut.

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    O'Brien, Heath E; Thakur, Shalabh; Gong, Yunchen; Fung, Pauline; Zhang, Jianfeng; Yuan, Lijie; Wang, Pauline W; Yong, Choseung; Scortichini, Marco; Guttman, David S

    2012-07-16

    Hazelnut (Corylus avellana) decline disease in Greece and Italy is caused by the convergent evolution of two distantly related lineages of Pseudomonas syringae pv. avellanae (Pav). We sequenced the genomes of three Pav isolates to determine if their convergent virulence phenotype had a common genetic basis due to either genetic exchange between lineages or parallel evolution. We found little evidence for horizontal transfer (recombination) of genes between Pav lineages, but two large genomic islands (GIs) have been recently acquired by one of the lineages. Evolutionary analyses of the genes encoding type III secreted effectors (T3SEs) that are translocated into host cells and are important for both suppressing and eliciting defense responses show that the two Pav lineages have dramatically different T3SE profiles, with only two shared putatively functional T3SEs. One Pav lineage has undergone unprecedented secretome remodeling, including the acquisition of eleven new T3SEs and the loss or pseudogenization of 15, including five of the six core T3SE families that are present in the other Pav lineage. Molecular dating indicates that divergence within both of the Pav lineages predates their observation in the field. This suggest that both Pav lineages have been cryptically infecting hazelnut trees or wild relatives for many years, and that the emergence of hazelnut decline in the 1970s may have been due to changes in agricultural practice. These data show that divergent lineages of P. syringae can converge on identical disease etiology on the same host plant using different virulence mechanisms and that dramatic shifts in the arsenal of T3SEs can accompany disease emergence.

  10. Negative Autogenous Control of the Master Type III Secretion System Regulator HrpL in Pseudomonas syringae

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    Christopher Waite

    2017-01-01

    Full Text Available The type III secretion system (T3SS is a principal virulence determinant of the model bacterial plant pathogen Pseudomonas syringae. T3SS effector proteins inhibit plant defense signaling pathways in susceptible hosts and elicit evolved immunity in resistant plants. The extracytoplasmic function sigma factor HrpL coordinates the expression of most T3SS genes. Transcription of hrpL is dependent on sigma-54 and the codependent enhancer binding proteins HrpR and HrpS for hrpL promoter activation. hrpL is oriented adjacently to and divergently from the HrpL-dependent gene hrpJ, sharing an intergenic upstream regulatory region. We show that association of the RNA polymerase (RNAP-HrpL complex with the hrpJ promoter element imposes negative autogenous control on hrpL transcription in P. syringae pv. tomato DC3000. The hrpL promoter was upregulated in a ΔhrpL mutant and was repressed by plasmid-borne hrpL. In a minimal Escherichia coli background, the activity of HrpL was sufficient to achieve repression of reconstituted hrpL transcription. This repression was relieved if both the HrpL DNA-binding function and the hrp-box sequence of the hrpJ promoter were compromised, implying dependence upon the hrpJ promoter. DNA-bound RNAP-HrpL entirely occluded the HrpRS and partially occluded the integration host factor (IHF recognition elements of the hrpL promoter in vitro, implicating inhibition of DNA binding by these factors as a cause of negative autogenous control. A modest increase in the HrpL concentration caused hypersecretion of the HrpA1 pilus protein but intracellular accumulation of later T3SS substrates. We argue that negative feedback on HrpL activity fine-tunes expression of the T3SS regulon to minimize the elicitation of plant defenses.

  11. Decreased abundance of type III secretion system-inducing signals in Arabidopsis mkp1 enhances resistance against Pseudomonas syringae

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    Anderson, Jeffrey C.; Wan, Ying; Kim, Young-Mo; Pasa-Tolic, Ljiljana; Metz, Thomas O.; Peck, Scott C.

    2014-04-21

    Many phytopathogenic bacteria use a type III secretion system (T3SS) to inject defense-suppressing effector proteins into host cells. Genes encoding the T3SS are induced at the start of infection, yet host signals that initiate T3SS gene expression are poorly understood. Here we identify several plant-derived metabolites that induce the T3SS in the bacterial pathogen Pseudomonas syringae pv tomato DC3000. In addition, we report that mkp1 (mapk phosphatase 1), an Arabidopsis mutant that is more resistant to bacterial infection, produces decreased levels of these T3SS-inducing metabolites. Consistent with the observed decrease in these metabolites, T3SS effector delivery by DC3000 was impaired in mkp1. Addition of the bioactive metabolites to the mkp1-DC3000 interaction fully restored T3SS effector delivery and suppressed enhanced resistance in mkp1. Together, these results demonstrate that DC3000 perceives multiple signals derived from plants to initiate their virulence program, and reveal a new layer of molecular communication between plants and these pathogenic bacteria.

  12. The Pseudomonas syringae type III effector AvrRpt2 functions downstream or independently of SA to promote virulence on Arabidopsis thaliana.

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    Chen, Zhongying; Kloek, Andrew P; Cuzick, Alayne; Moeder, Wolfgang; Tang, Dingzhong; Innes, Roger W; Klessig, Daniel F; McDowell, John M; Kunkel, Barbara N

    2004-02-01

    AvrRpt2, a Pseudomonas syringae type III effector protein, functions from inside plant cells to promote the virulence of P. syringae pv. tomato strain DC3000 (PstDC3000) on Arabidopsis thaliana plants lacking a functional copy of the corresponding RPS2 resistance gene. In this study, we extended our understanding of AvrRpt2 virulence activity by exploring the hypothesis that AvrRpt2 promotes PstDC3000 virulence by suppressing plant defenses. When delivered by PstDC3000, AvrRpt2 suppresses pathogen-related (PR) gene expression during infection, suggesting that AvrRpt2 suppresses defenses mediated by salicylic acid (SA). However, AvrRpt2 promotes PstDC3000 growth on transgenic plants expressing the SA-degrading enzyme NahG, indicating that AvrRpt2 does not promote bacterial virulence by modulating SA levels during infection. AvrRpt2 general virulence activity does not depend on the RPM1 resistance gene, as mutations in RPM1 had no effect on AvrRpt2-induced phenotypes. Transgenic plants expressing AvrRpt2 displayed enhanced susceptibility to PstDC3000 strains defective in type III secretion, indicating that enhanced susceptibility of these plants is not because of suppression of defense responses elicited by other type III effectors. Additionally, avrRpt2 transgenic plants did not exhibit increased susceptibility to Peronospora parasitica and Erysiphe cichoracearum, suggesting that AvrRpt2 virulence activity is specific to P. syringae.

  13. Functional and computational analysis of amino acid patterns predictive of type III secretion system substrates in Pseudomonas syringae

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    Bacterial type III secretion systems (T3SSs) deliver proteins called effectors into eukaryotic cells. Although N-terminal amino acid sequences are required for translocation, the mechanism of substrate recognition by the T3SS is unknown. Almost all actively deployed T3SS substrates in the plant path...

  14. Quantitative Interactor Screening with next-generation Sequencing (QIS-Seq identifies Arabidopsis thaliana MLO2 as a target of the Pseudomonas syringae type III effector HopZ2

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    Lewis Jennifer D

    2012-01-01

    Full Text Available Abstract Background Identification of protein-protein interactions is a fundamental aspect of understanding protein function. A commonly used method for identifying protein interactions is the yeast two-hybrid system. Results Here we describe the application of next-generation sequencing to yeast two-hybrid interaction screens and develop Quantitative Interactor Screen Sequencing (QIS-Seq. QIS-Seq provides a quantitative measurement of enrichment for each interactor relative to its frequency in the library as well as its general stickiness (non-specific binding. The QIS-Seq approach is scalable and can be used with any yeast two-hybrid screen and with any next-generation sequencing platform. The quantitative nature of QIS-Seq data make it amenable to statistical evaluation, and importantly, facilitates the standardization of experimental design, data collection, and data analysis. We applied QIS-Seq to identify the Arabidopsis thaliana MLO2 protein as a target of the Pseudomonas syringae type III secreted effector protein HopZ2. We validate the interaction between HopZ2 and MLO2 in planta and show that the interaction is required for HopZ2-associated virulence. Conclusions We demonstrate that QIS-Seq is a high-throughput quantitative interactor screen and validate MLO2 as an interactor and novel virulence target of the P. syringae type III secreted effector HopZ2.

  15. Draft genome sequences of pseudomonas syringae pv. syringae ALF3 isolated from alfalfa

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    We report the annotated draft genome of Pseudomonas syringae pv. syringae strain ALF3, isolated in Wyoming, USA. Comparison of this genome sequence with those of closely related strains of P. syringae pv. syringae adapted to other hosts will facilitate research into interactions between this pathoge...

  16. Bioinformatics Analysis of the Complete Genome Sequence of the Mango Tree Pathogen Pseudomonas syringae pv. syringae UMAF0158 Reveals Traits Relevant to Virulence and Epiphytic Lifestyle.

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    Pedro Manuel Martínez-García

    Full Text Available The genome sequence of more than 100 Pseudomonas syringae strains has been sequenced to date; however only few of them have been fully assembled, including P. syringae pv. syringae B728a. Different strains of pv. syringae cause different diseases and have different host specificities; so, UMAF0158 is a P. syringae pv. syringae strain related to B728a but instead of being a bean pathogen it causes apical necrosis of mango trees, and the two strains belong to different phylotypes of pv.syringae and clades of P. syringae. In this study we report the complete sequence and annotation of P. syringae pv. syringae UMAF0158 chromosome and plasmid pPSS158. A comparative analysis with the available sequenced genomes of other 25 P. syringae strains, both closed (the reference genomes DC3000, 1448A and B728a and draft genomes was performed. The 5.8 Mb UMAF0158 chromosome has 59.3% GC content and comprises 5017 predicted protein-coding genes. Bioinformatics analysis revealed the presence of genes potentially implicated in the virulence and epiphytic fitness of this strain. We identified several genetic features, which are absent in B728a, that may explain the ability of UMAF0158 to colonize and infect mango trees: the mangotoxin biosynthetic operon mbo, a gene cluster for cellulose production, two different type III and two type VI secretion systems, and a particular T3SS effector repertoire. A mutant strain defective in the rhizobial-like T3SS Rhc showed no differences compared to wild-type during its interaction with host and non-host plants and worms. Here we report the first complete sequence of the chromosome of a pv. syringae strain pathogenic to a woody plant host. Our data also shed light on the genetic factors that possibly determine the pathogenic and epiphytic lifestyle of UMAF0158. This work provides the basis for further analysis on specific mechanisms that enable this strain to infect woody plants and for the functional analysis of host

  17. Characterisation of the mgo operon in Pseudomonas syringae pv. syringae UMAF0158 that is required for mangotoxin production

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    2012-01-01

    Background Mangotoxin is an antimetabolite toxin that is produced by strains of Pseudomonas syringae pv. syringae; mangotoxin-producing strains are primarily isolated from mango tissues with symptoms of bacterial apical necrosis. The toxin is an oligopeptide that inhibits ornithine N-acetyl transferase (OAT), a key enzyme in the biosynthetic pathway of the essential amino acids ornithine and arginine. The involvement of a putative nonribosomal peptide synthetase gene (mgoA) in mangotoxin production and virulence has been reported. Results In the present study, we performed a RT-PCR analysis, insertional inactivation mutagenesis, a promoter expression analysis and terminator localisation to study the gene cluster containing the mgoA gene. Additionally, we evaluated the importance of mgoC, mgoA and mgoD in mangotoxin production. A sequence analysis revealed an operon-like organisation. A promoter sequence was located upstream of the mgoB gene and was found to drive lacZ transcription. Two terminators were located downstream of the mgoD gene. RT-PCR experiments indicated that the four genes (mgoBCAD) constitute a transcriptional unit. This operon is similar in genetic organisation to those in the three other P. syringae pathovars for which complete genomes are available (P. syringae pv. syringae B728a, P. syringae pv. tomato DC3000 and P. syringae pv. phaseolicola 1448A). Interestingly, none of these three reference strains is capable of producing mangotoxin. Additionally, extract complementation resulted in a recovery of mangotoxin production when the defective mutant was complemented with wild-type extracts. Conclusions The results of this study confirm that mgoB, mgoC, mgoA and mgoD function as a transcriptional unit and operon. While this operon is composed of four genes, only the last three are directly involved in mangotoxin production. PMID:22251433

  18. PsasM2I, a type II restriction-modification system in Pseudomonas savastanoi pv. savastanoi: differential distribution of carrier strains in the environment and the evolutionary history of homologous RM systems in the Pseudomonas syringae complex.

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    Cinelli, Tamara; Moscetti, Ilaria; Marchi, Guido

    2014-11-01

    A type II restriction-modification system was found in a native plasmid of Pseudomonas savastanoi pv. savastanoi MLLI2. Functional analysis of the methyltransferase showed that the enzyme acts by protecting the DNA sequence CTGCAG from cleavage. Restriction endonuclease expression in recombinant Escherichia coli cells resulted in mutations in the REase sequence or transposition of insertion sequence 1A in the coding sequence, preventing lethal gene expression. Population screening detected homologous RM systems in other P. savastanoi strains and in the Pseudomonas syringae complex. An epidemiological survey carried out by sampling olive and oleander knots in two Italian regions showed an uneven diffusion of carrier strains, whose presence could be related to a selective advantage in maintaining the RM system in particular environments or subpopulations. Moreover, carrier strains can coexist in the same orchards, plants, and knot tissues with non-carriers, revealing unexpected genetic variability on a very small spatial scale. Phylogenetic analysis of the RM system and housekeeping gene sequences in the P. syringae complex demonstrated the ancient acquisition of the RM systems. However, the evolutionary history of the gene complex also showed the involvement of horizontal gene transfer between related strains and recombination events.

  19. Extracytoplasmic function sigma factors in Pseudomonas syringae

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    Kiil, Kristoffer; Oguiza, J.A.; Ussery, D.W.

    2005-01-01

    Genome analyses of the plant pathogens Pseudomonas syringae pv. tomato DC3000, pv. syringae B728a and pv. phaseolicola 1448A reveal fewer extracytoplasmic function (ECF) sigma factors than in related Pseudomonads with different lifestyles. We highlight the presence of a P. syringae-specific ECF...

  20. Media pH and media type can significantly affect the reliability of in vitro copper-tolerance assessments of Pseudomonas syringae pv. tomato.

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    Griffin, Karina; Brown, Philip; Gambley, Cherie

    2018-03-07

    There are inconsistencies with in vitro copper-tolerance screening methodology for Pseudomonas syringae pv. tomato in the current literature, particularly in relation to the appropriate medium to use, copper-tolerance thresholds and reporting medium pH and/or pH adjustment steps. This study investigates the effect of medium and pH on copper-tolerance results, including the potential use of 2-(N-morpholino)ethanesulfonic acid (MES) buffer to stabilise media pH. Copper-tolerance methodology was investigated through in vitro and in vivo testing of P. syringae pv. tomato. Four different media were tested, Nutrient Agar (NA), Casitone Yeast Extract Glycerol Agar (CYEG), King's B medium (KB) and Potato Dextrose Agar (PDA). Highly variable copper-tolerance profiles were observed for different isolates on the media tested. A pH range of 5.8-7.0 produced consistent copper-tolerance data; outside of this range the data was unreliable. Addition of MES to media, buffered the pH to within the acceptable levels. Copper-tolerance thresholds with different media can vary significantly and the lowering effect of copper sulfate on media pH must be considered in media preparation. Methodology presented in the study can be extrapolated to copper-tolerance testing for other pathogenic plant bacteria, particularly other pseudomonads. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  1. The Ca2+ induced two-component system, CvsSR regulates the Type III secretion system and the extracytoplasmic function sigma-factor AlgU in Pseudomonas syringae pv. tomato DC3000.

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    Fishman, Maxwell R; Zhang, Johnson; Bronstein, Philip A; Stodghill, Paul; Filiatrault, Melanie J

    2017-12-20

    Two-component systems (TCSs) of bacteria regulate many different aspects of the bacterial life cycle including pathogenesis. Most TCSs remain uncharacterized with no information about the signal(s) or regulatory targets and/or role in bacterial pathogenesis. Here, we characterized a TCS in the plant-pathogenic bacterium Pseudomonas syringae pv. tomato DC3000 ( Pto ) composed of the histidine kinase, CvsS, and the response regulator, CvsR. CvsSR is necessary for virulence of Pto , since ΔcvsS and ΔcvsR strains produced fewer symptoms and demonstrated reduced growth on multiple hosts as compared to WT. We discovered that expression of cvsSR is induced by Ca 2+ concentrations found in leaf apoplastic fluid. Thus, Ca 2+ can be added to the list of signals that promote pathogenesis of Pto during host colonization. Through chromatin immunoprecipitation followed by next generation sequencing (ChIP-seq) and global transcriptome analysis (RNA-seq) we discerned the CvsR regulon. CvsR directly activated expression of the type III secretion system regulators, hrpR and hrpS , that regulates Pto virulence in a type III secretion system dependent manner. CvsR also indirectly repressed transcription of the extracytoplasmic sigma factor algU and production of alginate. Phenotypic analysis determined that CvsSR inversely regulated biofilm formation, swarming motility, and cellulose production in a Ca 2+ -dependent manner. Overall, our results show that CvsSR is a key regulatory hub critical for interaction with host plants. Importance Pathogenic bacteria must be able to react and respond to the surrounding environment, make use of available resources, and avert or counter host immune responses. Often, these abilities rely on two-component systems (TCSs) composed of interacting proteins that modulate gene expression. We identified a TCS in the plant-pathogenic bacterium Pseudomonas syringae that responds to the presence of calcium, which is an important signal during the plant

  2. The pathogenicity factor HrpF interacts with HrpA and HrpG to modulate type III secretion system (T3SS) function and t3ss expression in Pseudomonas syringae pv. averrhoi.

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    Huang, Yi-Chiao; Lin, Yuan-Chuen; Wei, Chia-Fong; Deng, Wen-Ling; Huang, Hsiou-Chen

    2016-09-01

    To ensure the optimal infectivity on contact with host cells, pathogenic Pseudomonas syringae has evolved a complex mechanism to control the expression and construction of the functional type III secretion system (T3SS) that serves as a dominant pathogenicity factor. In this study, we showed that the hrpF gene of P. syringae pv. averrhoi, which is located upstream of hrpG, encodes a T3SS-dependent secreted/translocated protein. Mutation of hrpF leads to the loss of bacterial ability on elicitation of disease symptoms in the host and a hypersensitive response in non-host plants, and the secretion or translocation of the tested T3SS substrates into the bacterial milieu or plant cells. Moreover, overexpression of hrpF in the wild-type results in delayed HR and reduced t3ss expression. The results of protein-protein interactions demonstrate that HrpF interacts directly with HrpG and HrpA in vitro and in vivo, and protein stability assays reveal that HrpF assists HrpA stability in the bacterial cytoplasm, which is reduced by a single amino acid substitution at the 67th lysine residue of HrpF with alanine. Taken together, the data presented here suggest that HrpF has two roles in the assembly of a functional T3SS: one by acting as a negative regulator, possibly involved in the HrpSVG regulation circuit via binding to HrpG, and the other by stabilizing HrpA in the bacterial cytoplasm via HrpF-HrpA interaction prior to the secretion and formation of Hrp pilus on the bacterial surface. © 2015 BSPP and John Wiley & Sons Ltd.

  3. Pseudomonas syringae – Pathogen of Sweet Cherry in Serbia

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    Veljko Gavrilović

    2012-01-01

    Full Text Available Characteristics of pathogenic Pseudomonas bacterial strains isolated from cherry inSerbia are presented in the article. Two types of symptoms were observed on cherry treesat few localities with intensive production in Serbia (Belgrade, Čačak, Topola, Šabac, NoviSad. The first symptom is bud necrosis and the second bacterial canker of cherry branch.Gram negative, fluorescent, oxidative bacterial strains were isolated from the margin ofnecrotic tissue. All investigated strains were levan and HR positive, while negative resultswere recorded for oxidase, pectinase and arginin dihydrolase tests (LOPAT+- - - +.Based on pathogenicity tests and differential GATT tests, investigated strains weredivided in two distinct groups: the first group consisted of strains isolated from necroticcherry branch which caused necrosis on artificially inoculated cherry, pear and lemon fruits,syringae leaves and bean pods, were gelatin and aesculin positive, and tyrosinase and tartratenegative (typical characteristics of P.s. pv. syringae. Contrary, second group strainswere isolated from necrotic cherry buds, showed negative results in mentioned pathogenicitytests, gelatin and aesculin tests were negative, while tyrosinase and tartrate werepositive (typical characteristics of P.s. pv. morsprunorum.REP PCR analyses showed that strains isolated from necrotic cherry buds belong to P. spv. morsprunorum compared to referent strain. In contrast, isolates obtained from necroticcherry branches had unique fingerprint profiles but different from all reference strains.According to the obtained results it was concluded that both pathovars of P. syringae(syringae and morsprunorum cause necrosis of cherry trees in Serbia.

  4. The PseEF efflux system is a virulence factor of Pseudomonas syringae pv. syringae.

    Science.gov (United States)

    Cho, Hyosun; Kang, Hyojeung

    2012-02-01

    An ATP-binding cassette (ABC) transporter, called the PseEF efflux system, was identified at the left border of the syr-syp genomic island of Pseudomonas syringae pv. syringae strain B301D. The PseEF efflux system was located within a 3.3-kb operon that encodes a periplasmic membrane fusion protein (PseE), and an ABC-type cytoplasmic membrane protein (PseF). The PseEF efflux system exhibited amino acid homology to a putative ABC efflux system (MacAB) of E. coli W3104 with identities of 47.2% (i.e., PseE to MacA) and 57.6% (i.e., PseF to MacB). A nonpolar mutation within the pseF gene was generated by nptII insertional mutagenesis. The resultant mutant strain showed significant reduction in secretion of syringomycin (74%) and syringopeptin (71%), as compared to parental strain B301D. Quantitative real-time RT-PCR was used to determine transcript levels of the syringomycin (syrB1) and syringopeptin (sypA) synthetase genes in strain B301D-HK7 (a pseF mutant). Expression of the sypA gene by mutant strain B301D-HK7 was approximately 6.9% as compared to that of parental strain B301D, while the syrB1 gene expression by mutant strain B301D-HK7 was nearly 14.6%. In addition, mutant strain B301D-HK7 was less virulent by approximately 67% than parental strain B301D in immature cherry fruits. Mutant strain B301D-HK7 was not reduced in resistance to any antibiotics used in this study as compared to parental strain B301D. Expression (transcript levels) of the pseF gene was induced approximately six times by strain B301D grown on syringomycin minimum medium (SRM) supplemented with the plant signal molecules arbutin and D-fructose (SRMAF), as compared to that of strain B301D grown on SRM (in the absence of plant signal molecules). In addition, during infection of bean plants by P. syringae pv. syringae strain B728a, expression of the pseF gene increased at 3 days after inoculation (dai). More than 180-fold induction was observed in transcript levels of the pseF gene by parental

  5. Deletions in the repertoire of Pseudomonas syringae pv. tomato DC3000 type III secretion effector genes reveal functional overlap among effectors

    Science.gov (United States)

    Many bacterial pathogens of plants and animals disarm and remodel host cells by injecting large repertoires of effectors via the type III secretion system (T3SS). The repertoires of individual strains appear to function as robust systems that can tolerate loss of individual effectors with little or ...

  6. Gene expression profiling in viable but nonculturable (VBNC cells of Pseudomonas syringae pv syringae

    Directory of Open Access Journals (Sweden)

    Olga A. Postnikova

    2015-12-01

    Full Text Available Pseudomonas syringae infects diverse crop plants and comprises at least 50 different pathovar strains with different host ranges. More information on the physiological and molecular effects of the host inhibitory environment on the pathogen is needed to develop resistant cultivars. Recently, we reported an in vitro model system that mimics the redox pulse associated with the oxidative burst in plant cells inoculated with Pseudomonas syringae pv. syringae. Using this system, we demonstrated that oxidation of acetosyringone, a major extracellular phenolic compound induced in some plants in response to bacteria, rendered Pseudomonas syringae. pv. syringae to a viable but nonculturable (VBNC state. Here we performed a large scale transcriptome profiling of P.s.pv. syringae in the VBNC state induced by acetosyringone treatment and identified bacterial genes and pathways presumably associated with this condition. The findings offer insight into what events occur when bacterial pathogens are first encountered and host defense responses are triggered. The acquired knowledge will improve our understanding of the molecular mechanisms of stress tolerance. We believe that this is the first work on global gene expression profiling of VBNC cells in plant pathogenic bacteria.

  7. Gene Expression Profiling in Viable but Nonculturable (VBNC) Cells of Pseudomonas syringae pv. syringae.

    Science.gov (United States)

    Postnikova, Olga A; Shao, Jonathan; Mock, Norton M; Baker, Con J; Nemchinov, Lev G

    2015-01-01

    Pseudomonas syringae infects diverse crop plants and comprises at least 50 different pathovar strains with different host ranges. More information on the physiological and molecular effects of the host inhibitory environment on the pathogen is needed to develop resistant cultivars. Recently, we reported an in vitro model system that mimics the redox pulse associated with the oxidative burst in plant cells inoculated with Pseudomonas syringae pv. syringae. Using this system, we demonstrated that oxidation of acetosyringone, a major extracellular phenolic compound induced in some plants in response to bacteria, rendered Pseudomonas syringae pv. syringae to a "viable but nonculturable" (VBNC) state. Here we performed a large scale transcriptome profiling of P. s. pv. syringae in the VBNC state induced by acetosyringone treatment and identified bacterial genes and pathways presumably associated with this condition. The findings offer insight into what events occur when bacterial pathogens are first encountered and host defense responses are triggered. The acquired knowledge will improve our understanding of the molecular mechanisms of stress tolerance. We believe that this is the first work on global gene expression profiling of VBNC cells in plant pathogenic bacteria.

  8. Induction of Callose Deposition in Tobacco (Nicotiana tabacum by Bacterial Lipopolysaccharide Pseudomonas syringae pv. tabaci and Pseudomonas syringae pv. glycinea

    Directory of Open Access Journals (Sweden)

    Pipit Marianingsih

    2014-12-01

    Full Text Available Lipopolysaccharide (LPS is a major component of outer-membrane gram-negative bacteria, and it can act as a Pathogen-Associated Molecular Pattern (PAMP for perception of pathogens by plants. LPS can be recognized by plants, triggering certain plant defense-related responses, including callose deposition. This study investigated induction of callose deposition by bacterial LPS in tobacco. Tobacco leaves were infiltrated with 400 μg/mL and 800 μg/mL LPS extracted from Pseudomonas syringae pv. tabaci (Pta and Pseudomonas syringae pv. glycinea (Pgl and incubated for 24 h or 48 h. To detect callose deposition, tobacco leaves were cleared in lactophenol solution, stained with aniline blue, and visualized by fluorescence microscopy. Results showed that LPS from Pgl induced more callose deposition in tobacco leaves than did that from Pta. In addition, a Pearson correlation test revealed that incubation period was the most significant factor in callose deposition, followed by the type of LPS bacteria. However, LPS concentration was not significantly corelated to callose deposition in tobacco leaves.

  9. Characterization of five ECF sigma factors in the genome of Pseudomonas syringae pv. syringae B728a.

    Directory of Open Access Journals (Sweden)

    Poulami Basu Thakur

    Full Text Available Pseudomonas syringae pv. syringae B728a, a bacterial pathogen of bean, utilizes large surface populations and extracellular signaling to initiate a fundamental change from an epiphytic to a pathogenic lifestyle. Extracytoplasmic function (ECF sigma (σ factors serve as important regulatory factors in responding to various environmental signals. Bioinformatic analysis of the B728a genome revealed 10 ECF sigma factors. This study analyzed deletion mutants of five previously uncharacterized ECF sigma factor genes in B728a, including three FecI-type ECF sigma factors (ECF5, ECF6, and ECF7 and two ECF sigma factors placed in groups ECF11 and ECF18. Transcriptional profiling by qRT-PCR analysis of ECF sigma factor mutants was used to measure expression of their associated anti-sigma and outer membrane receptor proteins, and expression of genes associated with production of extracellular polysaccharides, fimbriae, glycine betaine and syringomycin. Notably, the B728aΔecf7 mutant displayed reduced swarming and had decreased expression of CupC fimbrial genes. Growth and pathogenicity assays, using a susceptible bean host, revealed that none of the tested sigma factor genes are required for in planta growth and lesion formation.

  10. Spatial and temporal dynamics of primary and secondary metabolism in Phaseolus vulgaris challenged by Pseudomonas syringae.

    Science.gov (United States)

    Pérez-Bueno, María Luisa; Pineda, Mónica; Díaz-Casado, Elena; Barón, Matilde

    2015-01-01

    Many defense mechanisms contribute to the plant immune system against pathogens, involving the regulation of different processes of the primary and secondary metabolism. At the same time, pathogens have evolved mechanisms to hijack the plant defense in order to establish the infection and proliferate. Localization and timing of the host response are essential to understand defense mechanisms and resistance to pathogens (Rico et al. 2011). Imaging techniques, such as fluorescence imaging and thermography, are a very valuable tool providing spatial and temporal information about a series of plant processes. In this study, bean plants challenged with two pathovars of Pseudomonas syringae have been investigated. Pseudomonas syringae pv. phaseolicola 1448A and P. syringae pv. tomato DC3000 elicit a compatible and incompatible interaction in bean, respectively. Both types of host-pathogen interaction triggered different changes in the activity of photosynthesis and the secondary metabolism. We conclude that the combined analysis of leaf temperature, chlorophyll fluorescence and green fluorescence emitted by phenolics allows to discriminate compatible from incompatible P. syringae-Phaseolus vulgaris interactions in very early times of the infection, prior to the development of symptoms. These can constitute disease signatures that would allow an early identification of emerging plagues in crops. © 2014 Scandinavian Plant Physiology Society.

  11. Molecular characterization of Pseudomonas syringae pv. tomato isolates from Tanzania

    DEFF Research Database (Denmark)

    Shenge, K.C.; Stephan, D.; Mabagala, R. B.

    2008-01-01

    Bacterial speck caused by Pseudomonas syringae pv. tomato is an emerging disease of tomato in Tanzania. Following reports of outbreaks of the disease in many locations in Tanzania, 56 isolates of P. syringae pv. tomato were collected from four tomato- producing areas and characterized using patho...

  12. Resistant and susceptible responses in alfalfa (Medicago sativa) to bacterial stem blight caused by Pseudomonas syringae pv. syringae

    Science.gov (United States)

    Bacterial stem blight caused by Pseudomonas syringae pv. syringae is a common disease of alfalfa (Medicago sativa L.) in the central and western U.S. and has been reported in Australia and Europe. The disease is not always recognized because symptoms are often associated with frost damage. Two culti...

  13. Comparative genomic analysis of two-component regulatory proteins in Pseudomonas syringae

    DEFF Research Database (Denmark)

    Lavin, J.L.; Kiil, Kristoffer; Resano, O.

    2007-01-01

    Background: Pseudomonas syringae is a widespread bacterial plant pathogen, and strains of P. syringae may be assigned to different pathovars based on host specificity among different plant species. The genomes of P. syringae pv. syringae (Psy) B728a, pv. tomato (Pto) DC3000 and pv. phaseolicola...

  14. Dynamic evolution of pathogenicity revealed by sequencing and comparative genomics of 19 Pseudomonas syringae isolates.

    Directory of Open Access Journals (Sweden)

    David A Baltrus

    2011-07-01

    Full Text Available Closely related pathogens may differ dramatically in host range, but the molecular, genetic, and evolutionary basis for these differences remains unclear. In many Gram- negative bacteria, including the phytopathogen Pseudomonas syringae, type III effectors (TTEs are essential for pathogenicity, instrumental in structuring host range, and exhibit wide diversity between strains. To capture the dynamic nature of virulence gene repertoires across P. syringae, we screened 11 diverse strains for novel TTE families and coupled this nearly saturating screen with the sequencing and assembly of 14 phylogenetically diverse isolates from a broad collection of diseased host plants. TTE repertoires vary dramatically in size and content across all P. syringae clades; surprisingly few TTEs are conserved and present in all strains. Those that are likely provide basal requirements for pathogenicity. We demonstrate that functional divergence within one conserved locus, hopM1, leads to dramatic differences in pathogenicity, and we demonstrate that phylogenetics-informed mutagenesis can be used to identify functionally critical residues of TTEs. The dynamism of the TTE repertoire is mirrored by diversity in pathways affecting the synthesis of secreted phytotoxins, highlighting the likely role of both types of virulence factors in determination of host range. We used these 14 draft genome sequences, plus five additional genome sequences previously reported, to identify the core genome for P. syringae and we compared this core to that of two closely related non-pathogenic pseudomonad species. These data revealed the recent acquisition of a 1 Mb megaplasmid by a sub-clade of cucumber pathogens. This megaplasmid encodes a type IV secretion system and a diverse set of unknown proteins, which dramatically increases both the genomic content of these strains and the pan-genome of the species.

  15. Dynamic evolution of pathogenicity revealed by sequencing and comparative genomics of 19 Pseudomonas syringae isolates.

    Science.gov (United States)

    Baltrus, David A; Nishimura, Marc T; Romanchuk, Artur; Chang, Jeff H; Mukhtar, M Shahid; Cherkis, Karen; Roach, Jeff; Grant, Sarah R; Jones, Corbin D; Dangl, Jeffery L

    2011-07-01

    Closely related pathogens may differ dramatically in host range, but the molecular, genetic, and evolutionary basis for these differences remains unclear. In many Gram- negative bacteria, including the phytopathogen Pseudomonas syringae, type III effectors (TTEs) are essential for pathogenicity, instrumental in structuring host range, and exhibit wide diversity between strains. To capture the dynamic nature of virulence gene repertoires across P. syringae, we screened 11 diverse strains for novel TTE families and coupled this nearly saturating screen with the sequencing and assembly of 14 phylogenetically diverse isolates from a broad collection of diseased host plants. TTE repertoires vary dramatically in size and content across all P. syringae clades; surprisingly few TTEs are conserved and present in all strains. Those that are likely provide basal requirements for pathogenicity. We demonstrate that functional divergence within one conserved locus, hopM1, leads to dramatic differences in pathogenicity, and we demonstrate that phylogenetics-informed mutagenesis can be used to identify functionally critical residues of TTEs. The dynamism of the TTE repertoire is mirrored by diversity in pathways affecting the synthesis of secreted phytotoxins, highlighting the likely role of both types of virulence factors in determination of host range. We used these 14 draft genome sequences, plus five additional genome sequences previously reported, to identify the core genome for P. syringae and we compared this core to that of two closely related non-pathogenic pseudomonad species. These data revealed the recent acquisition of a 1 Mb megaplasmid by a sub-clade of cucumber pathogens. This megaplasmid encodes a type IV secretion system and a diverse set of unknown proteins, which dramatically increases both the genomic content of these strains and the pan-genome of the species. © 2011 Baltrus et al.

  16. Phosphatidylcholine absence affects the secretion of lipodepsipeptide phytoxins in Pseudomonas syringae pv. syringae van Hall CFCC 1336.

    Science.gov (United States)

    Cao, Fang; Xiong, Min; Li, Shunyi; Cai, Huawan; Sun, Yufang; Yang, Sheng; Liu, Xin; Zhu, Rong; Yu, Xuejing; Wang, Xingguo

    2018-01-01

    Pseudomonas syringae pv. syringae van Hall CFCC 1336 (Pss 1336) is the causal agent of bacterial disease of stone fruit trees, and also able to elicit hypersensitive response (HR) in non-host tobacco. It is known that this pathogen uses PCS-pathway to synthesize phosphatidylcholine (PC), and mutation of the pcs gene abolishes bacterial PC synthesis. Previous study also found that the 1336 pcs - mutant lacking PC in its membrane phospholipids was unable to secrete HrpZ harpin and elicit HR in non-host plants. In this study, we further analyzed virulence of lipodepsipeptide phytoxins of Pss 1336 wild type (pcs + ), the 1336RM (pcs-/+) and the 1336 pcs- mutant, and found that the 1336 pcs- mutant was unable to cause necrosis of Chinese date fruits and inhibit fungal growth. HPLC analysis also showed that the 1336 pcs- mutant markedly reduced its secretion of lipodepsipeptide phytoxins. Analysis of semi-quantitative RT-PCR revealed that PC presence or absence did not affect gene expressions of SyrD, PseABC and PseEF efflux systems at transcriptional level. However, western blotting assays found that PseE and PseF present only in the cytoplasmic fractions but undetectable in the membrane extract of the 1336 pcs- mutant. PC absence obviously interrupted the translocation of two membrane-associated proteins PseE and PseF from cytoplasm to cell membranes to form an intact PseEF efflux system in bacterial membranes. Failure to form PseEF efflux system could be a major factor for less lipopeptide-phytoxin secretion. Our results demonstrate that PC in bacterial membrane phospholipids plays an important role in maintaining physiological functions of PseEF efflux system. Copyright © 2017 Elsevier GmbH. All rights reserved.

  17. Systemic Induction of Salicylic Acid Accumulation in Cucumber after Inoculation with Pseudomonas syringae pv syringae 1

    Science.gov (United States)

    Rasmussen, Jack B.; Hammerschmidt, Raymond; Zook, Michael N.

    1991-01-01

    Inoculation of one true leaf of cucumber (Cucumis sativus L.) plants with Pseudomonas syringae pathovar syringae results in the systemic appearance of salicylic acid in the phloem exudates from petioles above, below, and at the site of inoculation. Analysis of phloem exudates from the petioles of leaves 1 and 2 demonstrated that the earliest increases in salicylic acid occurred 8 hours after inoculation of leaf 1 in leaf 1 and 12 hours after inoculation of leaf 1 in leaf 2. Detaching leaf 1 at intervals after inoculation demonstrated that leaf 1 must remain attached for only 4 hours after inoculation to result in the systemic accumulation of salicylic acid. Because the levels of salicylic acid in phloem exudates from leaf 1 did not increase to detectable levels until at least 8 hours after inoculation with P. s. pathovar syringae, the induction of increased levels of salicylic acid throughout the plant are presumably the result of another chemical signal generated from leaf 1 within 4 hours after inoculation. Injection of salicylic acid into tissues at concentrations found in the exudates induced resistance to disease and increased peroxidase activity. Our results support a role for salicylic acid as an endogenous inducer of resistance, but our data also suggest that salicylic acid is not the primary systemic signal of induced resistance in cucumber. ImagesFigure 2 PMID:16668554

  18. New strategies for genetic engineering Pseudomonas syringae using recombination

    Science.gov (United States)

    Here we report that DNA oligonucleotides (oligos) introduced directly into bacteria by electroporation can recombine with the bacterial chromosome. This phenomenon was identified in Pseudomonas syringae and we subsequently found that Escherichia coli, Salmonella typhimurium and Shigella flexneri are...

  19. Pseudomnas syringae – a Pathogen of Fruit Trees in Serbia

    Directory of Open Access Journals (Sweden)

    Veljko Gavrilović

    2009-01-01

    Full Text Available Data about symptomatology, pathogenicity and bacteriological characteristics of Pseudomonas syringae, and PCR methods for fast and reliable detection of the pathogen are given in this paper. P. syringae has been experimentaly proved as a pathogen of pear, apple, apricot, plum cherry, and raspberry, and pathogen strains have also been isolated from necrotic peach buds. Two pathogen varieties, syringae and morsprunorum, were found in our research in Serbia, the former being dominant on fruit trees.The most reliable method for detection of this bacteria is PCR, using BOX and REP primers. This method has also revealed significant differences among the strains originating from fruit trees in Serbia. Thus, it was proved that the population of P. syringae in Serbia is heterogeneous, which is very important for future epidemiologocal studies. Control of this pathogen includes mechanical, cultural and chemical measures, but integrated approach is very important for sustainable control.

  20. Differentiation of Pseudomonas syringae Pathovars Originating from Stone Fruits

    Directory of Open Access Journals (Sweden)

    Katarina Gašić

    2012-01-01

    Full Text Available Due to an overlapping host range, similar symptomatology and many common characteristics,Pseudomonas syringae pathovars originating from stone fruits can easily be misidentified.In order to select tests for rapid and efficient differentiation of P. s. pvs. syringae,morsprunorum and persicae, we studied the suitability and differentiating potential ofsome standard bacteriological and molecular methods. Differentiation of the strains wasperformed using LOPAT, GATTa and ice nucleation tests, nutrient sucrose broth growthand utilization of various carbon sources. PCR method enabled the detection of toxin-producinggenes: syrB and syrD in P. s. pv. syringae, and cfl gene in P. s. pv. morsprunorum race1. Syringomycin production by pv. syringae was confirmed in bioassay using Geotrichumcandidum, Saccharomyces cerevisiae and Rhodotorula pilimanae as indicator organisms.Pathogenicity test on lemon and immature nectarine fruits, as well as on string bean pods,showed different intensity of reaction of the inoculated material which could separate pv.syringae from the other two pathovars. PCR-based repetitive sequences, Rep-PCR withREP, ERIC and BOX primers revealed different genetic profiles within P. syringae pathovars.

  1. Disruption of the ammonium transporter AMT1.1 alters basal defences generating resistance against Pseudomonas syringae and Plectosphaerella cucumerina

    Directory of Open Access Journals (Sweden)

    Victoria ePastor

    2014-05-01

    Full Text Available Disruption of the high-affinity nitrate transporter NRT2.1 activates the priming defence against Pseudomonas syringae, resulting in enhanced resistance. In this study, it is demonstrated that the high-affinity ammonium transporter AMT1.1 is a negative regulator of Arabidopsis defence responses. The T-DNA knockout mutant amt1.1 displays enhanced resistance against Plectosphaerella cucumerina and reduced susceptibility to P. syringae. The impairment of AMT1.1 induces significant metabolic changes in the absence of challenge, suggesting that amt1.1 retains constitutive defence responses. Interestingly, amt1.1 combats pathogens differently depending on the lifestyle of the pathogen. In addition, N starvation enhances the susceptibility of wild type plants and the mutant amt1.1 to P. syringae whereas it has no effect on P. cucumerina resistance. The metabolic changes of amt1.1 against P. syringae are subtler and are restricted to the phenylpropanoid pathway, which correlates with its reduced susceptibility. By contrast, the amt1.1 mutant responds by activating higher levels of camalexin and callose against P. cucumerina. In addition, amt1.1 shows altered levels of aliphatic and indolic glucosinolates and other Trp-related compounds following infection by the necrotroph. These observations indicate that AMT1.1 may play additional roles that affect N uptake and plant immune responses.

  2. 40 CFR 180.1261 - Xanthomonas campestris pv. vesicatoria and Pseudomonas syringae pv. tomato specific Bacteriophages.

    Science.gov (United States)

    2010-07-01

    ... and Pseudomonas syringae pv. tomato specific Bacteriophages. 180.1261 Section 180.1261 Protection of.... vesicatoria and Pseudomonas syringae pv. tomato specific Bacteriophages. An exemption from the requirement of... syringae pv. tomato specific bacteriophages in or on pepper and tomato. [74 FR 26536, June 3, 2009] ...

  3. 40 CFR 180.1145 - Pseudomonas syringae; exemption from the requirement of a tolerance.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Pseudomonas syringae; exemption from... FOOD Exemptions From Tolerances § 180.1145 Pseudomonas syringae; exemption from the requirement of a tolerance. Pseudomonas syringae is exempted from the requirement of a tolerance on all raw agricultural...

  4. Information Management of Genome Enabled Data Streams for Pseudomonas syringae on the Pseudomonas-Plant Interaction (PPI Website

    Directory of Open Access Journals (Sweden)

    Magdalen Lindeberg

    2011-11-01

    Full Text Available Genome enabled research has led to a large and ever-growing body of data on Pseudomonas syringae genome variation and characteristics, though systematic capture of this information to maximize access by the research community remains a significant challenge. Major P. syringae data streams include genome sequence data, newly identified type III effectors, biological characterization data for type III effectors, and regulatory feature characterization. To maximize data access, the Pseudomonas-Plant Interaction (PPI website [1] is primarily focused on categorization of type III effectors and curation of effector functional data represented in the Hop database and Pseudomonas-Plant Interaction Resource, respectively. The PPI website further serves as a conduit for incorporation of new genome characterization data into the annotation records at NCBI and other data repositories, and clearinghouse for additional data sets and updates in response to the evolving needs of the research community.

  5. Phosphatidylcholine synthesis is essential for HrpZ harpin secretion in plant pathogenic Pseudomonas syringae and non-pathogenic Pseudomonas sp. 593.

    Science.gov (United States)

    Xiong, Min; Long, Deliang; He, Huoguang; Li, Yang; Li, Yadong; Wang, Xingguo

    2014-01-01

    Pseudomonas syringae pv. syringae van Hall is important phytopathogenic bacterium of stone fruit trees, and able to elicit hypersensitive response (HR) in nonhost plants. The HrpZ, secreted via type III secretion system (T3SS) to the extracellular space of the plant, is a T3SS-dependent protein and a sole T3SS effector able to induce the host defense response outside host cells. We deleted the phosphatidylcholine synthase gene (pcs) of P. syringae pv. syringae van Hall CFCC 1336, and found that the 1336 pcs(-) mutant was unable to synthesize phosphatidylcholine and elicit a typical HR in soybean. Further studies showed that the 1336 pcs(-) mutant was unable to secrete HrpZ harpin but could express HrpZ protein in cytoplasm as effectively as the wild type. To confirm if phosphatidylcholine affects HrpZ harpin secretion, we introduced the hrpZ gene into the soil-dwelling bacterium Pseudomonas sp. 593 and the 593 pcs(-) mutant, which were unable to express HrpZ harpin and elicit HR in tobacco or soybean. Western blotting and HR assay showed that the 593H not only secreted HrpZ harpin but also caused a strong HR in tobacco and soybean. In contrast, the 593 pcs(-)H only expressed HrpZ protein in its cytoplasm at the wild type level, but did not secrete HrpZ harpin or elicit HR reaction. Our results demonstrate that phosphatidylcholine is essential for the secretion of HrpZ harpin in P. syringae pv. syringae van Hall and other Pseudomonas strains. Copyright © 2013 Elsevier GmbH. All rights reserved.

  6. Differences between Pseudomonas syringae pv. syringae B728a and Pantoea agglomerans BRT98 in Epiphytic and Endophytic Colonization of Leaves

    Science.gov (United States)

    Sabaratnam, Siva; Beattie, Gwyn A.

    2003-01-01

    The leaf colonization strategies of two bacterial strains were investigated. The foliar pathogen Pseudomonas syringae pv. syringae strain B728a and the nonpathogen Pantoea agglomerans strain BRT98 were marked with a green fluorescent protein, and surface (epiphytic) and subsurface (endophytic) sites of bean and maize leaves in the laboratory and the field were monitored to see if populations of these strains developed. The populations were monitored using both fluorescence microscopy and counts of culturable cells recovered from nonsterilized and surface-sterilized leaves. The P. agglomerans strain exclusively colonized epiphytic sites on the two plant species. Under favorable conditions, the P. agglomerans strain formed aggregates that often extended over multiple epidermal cells. The P. syringae pv. syringae strain established epiphytic and endophytic populations on asymptomatic leaves of the two plant species in the field, with most of the P. syringae pv. syringae B728a cells remaining in epiphytic sites of the maize leaves and an increasing number occupying endophytic sites of the bean leaves in the 15-day monitoring period. The epiphytic P. syringae pv. syringae B728a populations appeared to originate primarily from multiplication in surface sites rather than from the movement of cells from subsurface to surface sites. The endophytic P. syringae pv. syringae B728a populations appeared to originate primarily from inward movement through the stomata, with higher levels of multiplication occurring in bean than in maize. A rainstorm involving a high raindrop momentum was associated with rapid growth of the P. agglomerans strain on both plant species and with rapid growth of both the epiphytic and endophytic populations of the P. syringae pv. syringae strain on bean but not with growth of the P. syringae pv. syringae strain on maize. These results demonstrate that the two bacterial strains employed distinct colonization strategies and that the epiphytic and

  7. Global analysis of the HrpL regulon in the plant pathogen Pseudomonas syringae pv. tomato DC3000 reveals new regulon members with diverse functions

    Science.gov (United States)

    The type III secretion system (T3SS) is required for virulence in the gram-negative plant pathogen Pseudomonas syringae pv. tomato DC3000. The alternative sigma factor HrpL directly regulates expression of T3SS genes via a consensus promoter sequence, often designated as the “hrp promoter.” Although...

  8. Genome-wide DNA binding pattern of two-component system response regulator RhpR in Pseudomonas syringae

    Directory of Open Access Journals (Sweden)

    Tianhong Zhou

    2015-06-01

    Full Text Available Although Pseudomonas syringae uses the two-component system RhpRS to modulate the expression of type III secretion system (T3SS genes and pathogenicity, the molecular mechanisms and the regulon of RhpRS have yet to be fully demonstrated. We have performed a genome-wide analysis of RhpR binding to DNA prepared from P. syringae pv. phaseolicola in order to identify candidate direct targets of RhpR-mediated transcriptional regulation, as described in our recent article [1]. The data are available from NCBI Gene Expression Omnibus (GEO with the accession number GSE58533. Here we describe the detailed methods and data analyses of our RhpR ChIP-seq dataset.

  9. Arabidopsis PECTIN METHYLESTERASEs contribute to immunity against Pseudomonas syringae.

    Science.gov (United States)

    Bethke, Gerit; Grundman, Rachael E; Sreekanta, Suma; Truman, William; Katagiri, Fumiaki; Glazebrook, Jane

    2014-02-01

    Pectins, major components of dicot cell walls, are synthesized in a heavily methylesterified form in the Golgi and are partially deesterified by pectin methylesterases (PMEs) upon export to the cell wall. PME activity is important for the virulence of the necrotrophic fungal pathogen Botrytis cinerea. Here, the roles of Arabidopsis PMEs in pattern-triggered immunity and immune responses to the necrotrophic fungus Alternaria brassicicola and the bacterial hemibiotroph Pseudomonas syringae pv maculicola ES4326 (Pma ES4326) were studied. Plant PME activity increased during pattern-triggered immunity and after inoculation with either pathogen. The increase of PME activity in response to pathogen treatment was concomitant with a decrease in pectin methylesterification. The pathogen-induced PME activity did not require salicylic acid or ethylene signaling, but was dependent on jasmonic acid signaling. In the case of induction by A. brassicicola, the ethylene response factor, but not the MYC2 branch of jasmonic acid signaling, contributed to induction of PME activity, whereas in the case of induction by Pma ES4326, both branches contributed. There are 66 PME genes in Arabidopsis, suggesting extensive genetic redundancy. Nevertheless, selected pme single, double, triple and quadruple mutants allowed significantly more growth of Pma ES4326 than wild-type plants, indicating a role of PMEs in resistance to this pathogen. No decreases in total PME activity were detected in these pme mutants, suggesting that the determinant of immunity is not total PME activity; rather, it is some specific effect of PMEs such as changes in the pattern of pectin methylesterification.

  10. Virulence of the Phytopathogen Pseudomonas syringae pv. Maculicola Is rpoN Dependent

    Science.gov (United States)

    Hendrickson, Erik L.; Guevera, Pablo; Peñaloza-Vàzquez, Alejandro; Shao, Jing; Bender, Carol; Ausubel, Frederick M.

    2000-01-01

    We cloned the rpoN (ntrA and glnF) gene encoding ς54 from the phytopathogen Pseudomonas syringae pv. maculicola strain ES4326. The P. syringae ES4326 rpoN gene complemented Pseudomonas aeruginosa, Escherichia coli, and Klebsiella aerogenes rpoN mutants for a variety of rpoN mutant phenotypes, including the inability to utilize nitrate as sole nitrogen source. DNA sequence analysis of the P. syringae ES4326 rpoN gene revealed that the deduced amino acid sequence was most similar (86% identity; 95% similarity) to the ς54 protein encoded by the Pseudomonas putida rpoN gene. A marker exchange protocol was used to construct an ES4326 rpoN insertional mutation, rpoN::Kmr. In contrast to wild-type ES4326, ES4326 rpoN::Kmr was nonmotile and could not utilize nitrate, urea, C4-dicarboxylic acids, several amino acids, or concentrations of ammonia below 2 mM as nitrogen sources. rpoN was essential for production of the phytotoxin coronatine and for expression of the structural genes encoding coronamic acid. In addition, ES4326 rpoN::Kmr did not multiply or elicit disease symptoms when infiltrated into Arabidopsis thaliana leaves, did not elicit the accumulation of several Arabidopsis defense-related mRNAs, and did not elicit a hypersensitive response (HR) when infiltrated into tobacco (Nicotiana tabacum) leaves. Furthermore, whereas P. syringae ES4326 carrying the avirulence gene avrRpt2 elicited an HR when infiltrated into Arabidopsis ecotype Columbia leaves, ES4326 rpoN::Kmr carrying avrRpt2 elicited no response. Constitutive expression of ES4326 hrpL in ES4326 rpoN::Kmr partially restored defense-related mRNA accumulation, showing a direct role for the hrp cluster in host defense gene induction in a compatible host-pathogen interaction. However, constitutive expression of hrpL in ES4326 rpoN::Kmr did not restore coronatine production, showing that coronatine biosynthesis requires factors other than hrpL. PMID:10852883

  11. A chloroplast DNA phylogeny of lilacs (Syringa, Oleaceae): plastome groups show a strong correlation with crossing groups.

    Science.gov (United States)

    Kim, K J; Jansen, R K

    1998-09-01

    Phylogenetic relationships and genomic compatibility were compared for 60 accessions of Syringa using chloroplast DNA (cpDNA) and nuclear ribosomal DNA (rDNA) markers. A total of 669 cpDNA variants, 653 of which were potentially phylogenetically informative, was detected using 22 restriction enzymes. Phylogenetic analyses reveal four strongly supported plastome groups that correspond to four genetically incompatible crossing groups. Relationships of the four plastome groups (I(II(III,IV))) correlate well with the infrageneric classification except for ser. Syringa and Pinnatifoliae. Group I, which includes subg. Ligustrina, forms a basal lineage within Syringa. Group II includes ser. Syringa and Pinnatifoliae and the two series have high compatibility and low sequence divergence. Group III consists of three well-defined species groups of ser. Pubescentes. Group IV comprises all members of ser. Villosae and has the lowest interspecific cpDNA sequence divergences. Comparison of cpDNA sequence divergence with crossability data indicates that hybrids have not been successfully generated between species with divergence greater than 0.7%. Hybrid barriers are strong among the four major plastome groups, which have sequence divergence estimates ranging from 1.096 to 1.962%. In contrast, fully fertile hybrids occur between species pairs with sequence divergence below 0.4%. Three regions of the plastome have length variants of greater than 100 bp, and these indels identify 12 different plastome types that correlate with phylogenetic trees produced from cpDNA restriction site data. Biparentally inherited nuclear rDNA and maternally inherited cpDNA length variants enable the identification of the specific parentage of several lilac hybrids.

  12. Arabidopsis heterotrimeric G-proteins play a critical role in host and nonhost resistance against Pseudomonas syringae pathogens.

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    Seonghee Lee

    Full Text Available Heterotrimeric G-proteins have been proposed to be involved in many aspects of plant disease resistance but their precise role in mediating nonhost disease resistance is not well understood. We evaluated the roles of specific subunits of heterotrimeric G-proteins using knock-out mutants of Arabidopsis Gα, Gβ and Gγ subunits in response to host and nonhost Pseudomonas pathogens. Plants lacking functional Gα, Gβ and Gγ1Gγ2 proteins displayed enhanced bacterial growth and disease susceptibility in response to host and nonhost pathogens. Mutations of single Gγ subunits Gγ1, Gγ2 and Gγ3 did not alter bacterial disease resistance. Some specificity of subunit usage was observed when comparing host pathogen versus nonhost pathogen. Overexpression of both Gα and Gβ led to reduced bacterial multiplication of nonhost pathogen P. syringae pv. tabaci whereas overexpression of Gβ, but not of Gα, resulted in reduced bacterial growth of host pathogen P. syringae pv. maculicola, compared to wild-type Col-0. Moreover, the regulation of stomatal aperture by bacterial pathogens was altered in Gα and Gβ mutants but not in any of the single or double Gγ mutants. Taken together, these data substantiate the critical role of heterotrimeric G-proteins in plant innate immunity and stomatal modulation in response to P. syringae.

  13. Extensive Field Survey, Laboratory and Greenhouse Studies Reveal Complex Nature of Pseudomonas syringae-Associated Hazelnut Decline in Central Italy.

    Science.gov (United States)

    Lamichhane, Jay Ram; Bartoli, Claudia; Varvaro, Leonardo

    2016-01-01

    Pseudomonas avellanae (Pav) has been reported as the causal agent of bacterial decline and bacterial canker of hazelnut in Italy and Greece, respectively. Both hazelnut diseases were reported to be similar in terms of symptoms, severity and persistence. In this study, we found that both symptomatic and asymptomatic trees in the field were colonized by Pav. Multilocus Sequence Typing (MLST) analysis showed that Pav strains isolated during this study in Italy belong to the P. syringae phylogroup 1 and they are closely related to Pav strains previously isolated in Greece from hazelnut bacterial canker. On the other hand, strains isolated in earlier studies from hazelnut decline in Italy belong to both phylogroup 1 and 2 of P. syringae. Both phylogroup 1 strains of P. syringae from Greece and Italy are different than strains isolated in this study in terms of their capacity to excrete fluorescent pigments on different media. Despite the same plant genotype and cropping practices adopted, the incidence of hazelnut decline ranged from nearly 0 to 91% across our study sites. No disease developed on plants inoculated with Pav through wounding while leaf scar inoculations produced only mild disease symptoms. Based on our results and the previously reported correlation between pedo-climatic conditions and hazelnut decline, we conclude that hazelnut decline in central Italy could be incited by a combination of predisposing (adverse pedo-climatic conditions) and contributing factors (Pav). Because this is a true decline different from "bacterial canker" described in Greece, we refer to it as hazelnut decline (HD).

  14. Characterization of a resistance-nodulation-cell division transporter system associated with the syr-syp genomic island of Pseudomonas syringae pv. syringae.

    Science.gov (United States)

    Kang, Hyojeung; Gross, Dennis C

    2005-09-01

    A tripartite resistance-nodulation-cell division (RND) transporter system, called the PseABC efflux system, was identified at the left border of the syr-syp genomic island of Pseudomonas syringae pv. syringae strain B301D. The PseABC efflux system was located within a 5.7-kb operon that encodes an outer membrane protein (PseA), a periplasmic membrane fusion protein (PseB), and an RND-type cytoplasmic membrane protein (PseC). The PseABC efflux system exhibited amino acid homology to a putative RND efflux system of Ralstonia solanacearum, with identities of 48% for PseA, 51% for PseB, and 61% for PseC. A nonpolar mutation within the pseC gene was generated by nptII insertional mutagenesis. The resultant mutant strain showed a larger reduction in syringopeptin secretion (67%) than in syringomycin secretion (41%) compared to parental strain B301D (P system controls expression of the pseA gene. Quantitative real-time reverse transcription-PCR was used to determine transcript levels of the syringomycin (syrB1) and syringopeptin (sypA) synthetase genes in strain B301D-HK4 (a pseC mutant). The expression of the sypA gene by mutant strain B301D-HK4 corresponded to approximately 13% of that by parental strain B301D, whereas the syrB1 gene expression by mutant strain B301D-HK4 was nearly 61% (P resistance of mutant strain B301D-HK4 to any antibiotic used in this study was not reduced compared to parental strain B301D, a drug-supersensitive acrB mutant of Escherichia coli showed two- to fourfold-increased resistance to acriflavine, erythromycin, and tetracycline upon heterologous expression of the pseA, pseB, and pseC genes (pseABC efflux genes). The PseABC efflux system is the first RND transporter system described for P. syringae, and it has an important role in secretion of syringomycin and syringopeptin.

  15. Evading plant immunity: feedback control of the T3SS inPseudomonas syringae.

    Science.gov (United States)

    Waite, Christopher; Schumacher, Jörg; Jovanovic, Milija; Bennett, Mark; Buck, Martin

    2017-03-17

    Microbes are responsible for over 10% of the global yield losses in staple crops such as wheat, rice, and maize. Understanding the decision-making strategies that enable bacterial plant pathogens to evade the host immune system and cause disease is essential for managing their ever growing threat to food security. Many utilise the needle-like type III secretion system (T3SS) to suppress plant immunity, by injecting effector proteins that inhibit eukaryotic signalling pathways into the host cell cytoplasm. Plants can in turn evolve resistance to specific pathogens via recognition and blocking of the T3SS effectors, so leading to an ongoing co-evolutionary 'arms race' between pathogen and host pairs. The extracytoplasmic function sigma factor HrpL co-ordinates the expression of the T3SS regulon in the leaf-dwelling Pseudomonas syringae and similar pathogens. Recently, we showed that association of HrpL with a target promoter directly adjacent to the hrpL gene imposes negative autogenous control on its own expression level due to overlapping regulatory elements. Our results suggest that by down-regulating T3SS function, this fine-tuning mechanism enables P. syringae to minimise effector-mediated elicitation of plant immunity.

  16. Evading plant immunity: feedback control of the T3SS in Pseudomonas syringae

    Directory of Open Access Journals (Sweden)

    Christopher Waite

    2017-03-01

    Full Text Available Microbes are responsible for over 10% of the global yield losses in staple crops such as wheat, rice, and maize. Understanding the decision-making strategies that enable bacterial plant pathogens to evade the host immune system and cause disease is essential for managing their ever growing threat to food security. Many utilise the needle-like type III secretion system (T3SS to suppress plant immunity, by injecting effector proteins that inhibit eukaryotic signalling pathways into the host cell cytoplasm. Plants can in turn evolve resistance to specific pathogens via recognition and blocking of the T3SS effectors, so leading to an ongoing co-evolutionary ‘arms race’ between pathogen and host pairs. The extracytoplasmic function sigma factor HrpL co-ordinates the expression of the T3SS regulon in the leaf-dwelling Pseudomonas syringae and similar pathogens. Recently, we showed that association of HrpL with a target promoter directly adjacent to the hrpL gene imposes negative autogenous control on its own expression level due to overlapping regulatory elements. Our results suggest that by down-regulating T3SS function, this fine-tuning mechanism enables P. syringae to minimise effector-mediated elicitation of plant immunity.

  17. Clarification of Taxonomic Status within the Pseudomonas syringae Species Group Based on a Phylogenomic Analysis

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    Margarita Gomila

    2017-12-01

    Full Text Available The Pseudomonas syringae phylogenetic group comprises 15 recognized bacterial species and more than 60 pathovars. The classification and identification of strains is relevant for practical reasons but also for understanding the epidemiology and ecology of this group of plant pathogenic bacteria. Genome-based taxonomic analyses have been introduced recently to clarify the taxonomy of the whole genus. A set of 139 draft and complete genome sequences of strains belonging to all species of the P. syringae group available in public databases were analyzed, together with the genomes of closely related species used as outgroups. Comparative genomics based on the genome sequences of the species type strains in the group allowed the delineation of phylogenomic species and demonstrated that a high proportion of strains included in the study are misclassified. Furthermore, representatives of at least 7 putative novel species were detected. It was also confirmed that P. ficuserectae, P. meliae, and P. savastanoi are later synonyms of P. amygdali and that “P. coronafaciens” should be revived as a nomenspecies.

  18. Genomic plasticity enables phenotypic variation of Pseudomonas syringae pv. tomato DC3000.

    Directory of Open Access Journals (Sweden)

    Zhongmeng Bao

    Full Text Available Whole genome sequencing revealed the presence of a genomic anomaly in the region of 4.7 to 4.9 Mb of the Pseudomonas syringae pv. tomato (Pst DC3000 genome. The average read depth coverage of Pst DC3000 whole genome sequencing results suggested that a 165 kb segment of the chromosome had doubled in copy number. Further analysis confirmed the 165 kb duplication and that the two copies were arranged as a direct tandem repeat. Examination of the corresponding locus in Pst NCPPB1106, the parent strain of Pst DC3000, suggested that the 165 kb duplication most likely formed after the two strains diverged via transposition of an ISPsy5 insertion sequence (IS followed by unequal crossing over between ISPsy5 elements at each end of the duplicated region. Deletion of one copy of the 165 kb region demonstrated that the duplication facilitated enhanced growth in some culture conditions, but did not affect pathogenic growth in host tomato plants. These types of chromosomal structures are predicted to be unstable and we have observed resolution of the 165 kb duplication to single copy and its subsequent re-duplication. These data demonstrate the role of IS elements in recombination events that facilitate genomic reorganization in P. syringae.

  19. Pseudomonas syringae pv. syringae uses proteasome inhibitor syringolin A to colonize from wound infection sites.

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    Johana C Misas-Villamil

    2013-03-01

    Full Text Available Infection of plants by bacterial leaf pathogens at wound sites is common in nature. Plants defend wound sites to prevent pathogen invasion, but several pathogens can overcome spatial restriction and enter leaf tissues. The molecular mechanisms used by pathogens to suppress containment at wound infection sites are poorly understood. Here, we studied Pseudomonas syringae strains causing brown spot on bean and blossom blight on pear. These strains exist as epiphytes that can cause disease upon wounding caused by hail, sand storms and frost. We demonstrate that these strains overcome spatial restriction at wound sites by producing syringolin A (SylA, a small molecule proteasome inhibitor. Consequently, SylA-producing strains are able to escape from primary infection sites and colonize adjacent tissues along the vasculature. We found that SylA diffuses from the primary infection site and suppresses acquired resistance in adjacent tissues by blocking signaling by the stress hormone salicylic acid (SA. Thus, SylA diffusion creates a zone of SA-insensitive tissue that is prepared for subsequent colonization. In addition, SylA promotes bacterial motility and suppresses immune responses at the primary infection site. These local immune responses do not affect bacterial growth and were weak compared to effector-triggered immunity. Thus, SylA facilitates colonization from wounding sites by increasing bacterial motility and suppressing SA signaling in adjacent tissues.

  20. Silencing and heterologous expression of ppo-2 indicate a specific function of a single polyphenol oxidase isoform in resistance of dandelion (Taraxacum officinale) against Pseudomonas syringae pv. tomato.

    Science.gov (United States)

    Richter, Carolin; Dirks, Mareike E; Gronover, Christian Schulze; Prüfer, Dirk; Moerschbacher, Bruno M

    2012-02-01

    Dandelion (Taraxacum officinale) possesses an unusually high degree of disease resistance. As this plant exhibits high polyphenol oxidase (PPO) activity and PPO have been implicated in resistance against pests and pathogens, we analyzed the potential involvement of five PPO isoenzymes in the resistance of dandelion against Botrytis cinerea and Pseudomonas syringae pv. tomato. Only one PPO (ppo-2) was induced during infection, and ppo-2 promoter and β-glucuronidase marker gene fusions revealed strong induction of the gene surrounding lesions induced by B. cinerea. Specific RNAi silencing reduced ppo-2 expression only, and concomitantly increased plant susceptibility to P. syringae pv. tomato. At 4 days postinoculation, P. syringae pv. tomato populations were strongly increased in the ppo-2 RNAi lines compared with wild-type plants. When the dandelion ppo-2 gene was expressed in Arabidopsis thaliana, a plant having no PPO gene, active protein was formed and protein extracts of the transgenic plants exhibited substrate-dependent antimicrobial activity against P. syringae pv. tomato. These results clearly indicate a strong contribution of a specific, single PPO isoform to disease resistance. Therefore, we propose that specific PPO isoenzymes be included in a new family of pathogenesis-related (PR) proteins.

  1. Flagellar motility confers epiphytic fitness advantages upon Pseudomonas syringae

    International Nuclear Information System (INIS)

    Haefele, D.M.; Lindow, S.E.

    1987-01-01

    The role of flagellar motility in determining the epiphytic fitness of an ice-nucleation-active strain of Pseudomonas syringae was examined. The loss of flagellar motility reduced the epiphytic fitness of a normally motile P. syringae strain as measured by its growth, survival, and competitive ability on bean leaf surfaces. Equal population sizes of motile parental or nonmotile mutant P. syringae strains were maintained on bean plants for at least 5 days following the inoculation of fully expanded primary leaves. However, when bean seedlings were inoculated before the primary leaves had expanded and bacterial populations on these leaves were quantified at full expansion, the population size of the nonmotile derivative strain reached only 0.9% that of either the motile parental or revertant strain. When fully expanded bean primary leaves were coinoculated with equal numbers of motile and nonmotile cells, the population size of a nonmotile derivative strain was one-third of that of the motile parental or revertant strain after 8 days. Motile and nonmotile cells were exposed in vitro and on plants to UV radiation and desiccating conditions. The motile and nonmotile strains exhibited equal resistance to both stresses in vitro. However, the population size of a nonmotile strain on leaves was less than 20% that of a motile revertant strain when sampled immediately after UV irradiation. Epiphytic populations of both motile and nonmotile P. syringae declined under desiccating conditions on plants, and after 8 days, the population size of a nonmotile strain was less than one-third that of the motile parental or revertant strain

  2. Miniature Transposable Sequences Are Frequently Mobilized in the Bacterial Plant Pathogen Pseudomonas syringae pv. phaseolicola

    Science.gov (United States)

    Bardaji, Leire; Añorga, Maite; Jackson, Robert W.; Martínez-Bilbao, Alejandro; Yanguas-Casás, Natalia; Murillo, Jesús

    2011-01-01

    Mobile genetic elements are widespread in Pseudomonas syringae, and often associate with virulence genes. Genome reannotation of the model bean pathogen P. syringae pv. phaseolicola 1448A identified seventeen types of insertion sequences and two miniature inverted-repeat transposable elements (MITEs) with a biased distribution, representing 2.8% of the chromosome, 25.8% of the 132-kb virulence plasmid and 2.7% of the 52-kb plasmid. Employing an entrapment vector containing sacB, we estimated that transposition frequency oscillated between 2.6×10−5 and 1.1×10−6, depending on the clone, although it was stable for each clone after consecutive transfers in culture media. Transposition frequency was similar for bacteria grown in rich or minimal media, and from cells recovered from compatible and incompatible plant hosts, indicating that growth conditions do not influence transposition in strain 1448A. Most of the entrapped insertions contained a full-length IS801 element, with the remaining insertions corresponding to sequences smaller than any transposable element identified in strain 1448A, and collectively identified as miniature sequences. From these, fragments of 229, 360 and 679-nt of the right end of IS801 ended in a consensus tetranucleotide and likely resulted from one-ended transposition of IS801. An average 0.7% of the insertions analyzed consisted of IS801 carrying a fragment of variable size from gene PSPPH_0008/PSPPH_0017, showing that IS801 can mobilize DNA in vivo. Retrospective analysis of complete plasmids and genomes of P. syringae suggests, however, that most fragments of IS801 are likely the result of reorganizations rather than one-ended transpositions, and that this element might preferentially contribute to genome flexibility by generating homologous regions of recombination. A further miniature sequence previously found to affect host range specificity and virulence, designated MITEPsy1 (100-nt), represented an average 2.4% of the total

  3. Apoplastic peroxidases are required for salicylic acid-mediated defense against Pseudomonas syringae.

    Science.gov (United States)

    Mammarella, Nicole D; Cheng, Zhenyu; Fu, Zheng Qing; Daudi, Arsalan; Bolwell, G Paul; Dong, Xinnian; Ausubel, Frederick M

    2015-04-01

    Reactive oxygen species (ROS) generated by NADPH oxidases or apoplastic peroxidases play an important role in the plant defense response. Diminished expression of at least two Arabidopsis thaliana peroxidase encoding genes, PRX33 (At3g49110) and PRX34 (At3g49120), as a consequence of anti-sense expression of a heterologous French bean peroxidase gene (asFBP1.1), were previously shown to result in reduced levels of ROS following pathogen attack, enhanced susceptibility to a variety of bacterial and fungal pathogens, and reduced levels of callose production and defense-related gene expression in response to the microbe associated molecular pattern (MAMP) molecules flg22 and elf26. These data demonstrated that the peroxidase-dependent oxidative burst plays an important role in the elicitation of pattern-triggered immunity (PTI). Further work reported in this paper, however, shows that asFBP1.1 antisense plants are not impaired in all PTI-associated responses. For example, some but not all flg22-elicited genes are induced to lower levels by flg22 in asFPB1.1, and callose deposition in asFPB1.1 is similar to wild-type following infiltration with a Pseudomonas syringae hrcC mutant or with non-host P. syringae pathovars. Moreover, asFPB1.1 plants did not exhibit any apparent defect in their ability to mount a hypersensitive response (HR). On the other hand, salicylic acid (SA)-mediated activation of PR1 was dramatically impaired in asFPB1.1 plants. In addition, P. syringae-elicited expression of many genes known to be SA-dependent was significantly reduced in asFBP1.1 plants. Consistent with this latter result, in asFBP1.1 plants the key regulator of SA-mediated responses, NPR1, showed both dramatically decreased total protein abundance and a failure to monomerize, which is required for its translocation into the nucleus. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. HOPM1 mediated disease resistance to Pseudomonas syringae in Arabidopsis

    Science.gov (United States)

    He, Sheng Yang [Okemos, MI; Nomura, Kinya [East Lansing, MI

    2011-11-15

    The present invention relates to compositions and methods for enhancing plant defenses against pathogens. More particularly, the invention relates to enhancing plant immunity against bacterial pathogens, wherein HopM1.sub.1-300 mediated protection is enhanced, such as increased protection to Pseudomonas syringae pv. tomato DC3000 HopM1 and/or there is an increase in activity of an ATMIN associated plant protection protein, such as ATMIN7. Reagents of the present invention further provide a means of studying cellular trafficking while formulations of the present inventions provide increased pathogen resistance in plants.

  5. Extensive Field Survey, Laboratory and Greenhouse Studies Reveal Complex Nature of Pseudomonas syringae-Associated Hazelnut Decline in Central Italy.

    Directory of Open Access Journals (Sweden)

    Jay Ram Lamichhane

    Full Text Available Pseudomonas avellanae (Pav has been reported as the causal agent of bacterial decline and bacterial canker of hazelnut in Italy and Greece, respectively. Both hazelnut diseases were reported to be similar in terms of symptoms, severity and persistence. In this study, we found that both symptomatic and asymptomatic trees in the field were colonized by Pav. Multilocus Sequence Typing (MLST analysis showed that Pav strains isolated during this study in Italy belong to the P. syringae phylogroup 1 and they are closely related to Pav strains previously isolated in Greece from hazelnut bacterial canker. On the other hand, strains isolated in earlier studies from hazelnut decline in Italy belong to both phylogroup 1 and 2 of P. syringae. Both phylogroup 1 strains of P. syringae from Greece and Italy are different than strains isolated in this study in terms of their capacity to excrete fluorescent pigments on different media. Despite the same plant genotype and cropping practices adopted, the incidence of hazelnut decline ranged from nearly 0 to 91% across our study sites. No disease developed on plants inoculated with Pav through wounding while leaf scar inoculations produced only mild disease symptoms. Based on our results and the previously reported correlation between pedo-climatic conditions and hazelnut decline, we conclude that hazelnut decline in central Italy could be incited by a combination of predisposing (adverse pedo-climatic conditions and contributing factors (Pav. Because this is a true decline different from "bacterial canker" described in Greece, we refer to it as hazelnut decline (HD.

  6. Extensive Field Survey, Laboratory and Greenhouse Studies Reveal Complex Nature of Pseudomonas syringae-Associated Hazelnut Decline in Central Italy

    Science.gov (United States)

    Lamichhane, Jay Ram; Bartoli, Claudia; Varvaro, Leonardo

    2016-01-01

    Pseudomonas avellanae (Pav) has been reported as the causal agent of bacterial decline and bacterial canker of hazelnut in Italy and Greece, respectively. Both hazelnut diseases were reported to be similar in terms of symptoms, severity and persistence. In this study, we found that both symptomatic and asymptomatic trees in the field were colonized by Pav. Multilocus Sequence Typing (MLST) analysis showed that Pav strains isolated during this study in Italy belong to the P. syringae phylogroup 1 and they are closely related to Pav strains previously isolated in Greece from hazelnut bacterial canker. On the other hand, strains isolated in earlier studies from hazelnut decline in Italy belong to both phylogroup 1 and 2 of P. syringae. Both phylogroup 1 strains of P. syringae from Greece and Italy are different than strains isolated in this study in terms of their capacity to excrete fluorescent pigments on different media. Despite the same plant genotype and cropping practices adopted, the incidence of hazelnut decline ranged from nearly 0 to 91% across our study sites. No disease developed on plants inoculated with Pav through wounding while leaf scar inoculations produced only mild disease symptoms. Based on our results and the previously reported correlation between pedo-climatic conditions and hazelnut decline, we conclude that hazelnut decline in central Italy could be incited by a combination of predisposing (adverse pedo-climatic conditions) and contributing factors (Pav). Because this is a true decline different from “bacterial canker” described in Greece, we refer to it as hazelnut decline (HD). PMID:26840951

  7. Validation of RT-qPCR Approaches to Monitor Pseudomonas syringae Gene Expression During Infection and Exposure to Pattern-Triggered Immunity.

    Science.gov (United States)

    Smith, Amy; Lovelace, Amelia H; Kvitko, Brian H

    2018-04-01

    Pseudomonas syringae pv. tomato DC3000 is an important model plant pathogen, with a fully annotated genome and multiple compatible plant hosts. Very few studies have examined the regulation of DC3000 gene expression in vivo. We developed a quantitative reverse transcription-polymerase chain reaction assay to monitor transcriptional changes in DC3000 inoculated into Arabidopsis thaliana leaves during disease and exposure to pattern-triggered immunity (PTI). In our approach, bacterial RNA concentrations in total tissue RNA are standardized using P. syringae-specific 16S ribosomal RNA primers. We validated multiple stable reference genes for normalization in calculating the relative expression of genes of interest. We used empirically derived rates of amplification efficiency to calculate relative expression of key marker genes for virulence-associated regulation. We demonstrated that exposure to PTI alters DC3000 expression of type III secretion system, coronatine synthesis genes, and flagellar marker genes.

  8. Dual Effect of the Cubic Ag₃PO₄ Crystal on Pseudomonas syringae Growth and Plant Immunity

    Directory of Open Access Journals (Sweden)

    Mi Kyung Kim

    2016-04-01

    Full Text Available We previously found that the antibacterial activity of silver phosphate crystals on Escherichia coli depends on their structure. We here show that the cubic form of silver phosphate crystal (SPC can also be applied to inhibit the growth of a plant-pathogenic Pseudomonas syringae bacterium. SPC pretreatment resulted in reduced in planta multiplication of P. syringae. Induced expression of a plant defense marker gene PR1 by SPC alone is suggestive of its additional plant immunity-stimulating activity. Since SPC can simultaneously inhibit P. syringae growth and induce plant defense responses, it might be used as a more effective plant disease-controlling agent.

  9. Chemical and Metabolic Aspects of Antimetabolite Toxins Produced by Pseudomonas syringae Pathovars

    Directory of Open Access Journals (Sweden)

    Eva Arrebola

    2011-08-01

    Full Text Available Pseudomonas syringae is a phytopathogenic bacterium present in a wide variety of host plants where it causes diseases with economic impact. The symptoms produced by Pseudomonas syringae include chlorosis and necrosis of plant tissues, which are caused, in part, by antimetabolite toxins. This category of toxins, which includes tabtoxin, phaseolotoxin and mangotoxin, is produced by different pathovars of Pseudomonas syringae. These toxins are small peptidic molecules that target enzymes of amino acids’ biosynthetic pathways, inhibiting their activity and interfering in the general nitrogen metabolism. A general overview of the toxins’ chemistry, biosynthesis, activity, virulence and potential applications will be reviewed in this work.

  10. Homeopathic Treatment of Arabidopsis thaliana Plants Infected with Pseudomonas syringae

    Directory of Open Access Journals (Sweden)

    Devika Shah-Rossi

    2009-01-01

    Full Text Available Homeopathic basic research is still in the screening phase to identify promising model systems that are adapted to the needs and peculiarities of homeopathic medicine and pharmacy. We investigated the potential of a common plant-pathogen system, Arabidopsis thaliana infected with the virulent bacteria Pseudomonas syringae, regarding its response towards a homeopathic treatment. A. thaliana plants were treated with homeopathic preparations before and after infection. Outcome measure was the number of P. syringae bacteria in the leaves of A. thaliana, assessed in randomized and blinded experiments. After a screening of 30 homeopathic preparations, we investigated the effect of Carbo vegetabilis 30x, Magnesium phosphoricum 30x, Nosode 30x, Biplantol (a homeopathic complex remedy, and Biplantol 30x on the infection rate in five or six independent experiments in total. The screening yielded significant effects for four out of 30 tested preparations. In the repeated experimental series, only the homeopathic complex remedy Biplantol induced a significant reduction of the infection rate (p = 0.01; effect size, d = 0.38. None of the other four repeatedly tested preparations (Carbo vegetabilis 30x, Magnesium phosphoricum 30x, Nosode 30x, Biplantol 30x yielded significant effects in the overall evaluation. This phytopathological model yielded a small to medium effect size and thus might be of interest for homeopathic basic research after further improvement. Compared to Bion (a common SAR inducer used as positive control, the magnitude of the treatment effect of Biplantol was about 50%. Thus, homeopathic formulations might have a potential for the treatment of plant diseases after further optimization. However, the ecological impact should be investigated more closely before widespread application.

  11. Transgenic tomato plants overexpressing tyramine N-hydroxycinnamoyltransferase exhibit elevated hydroxycinnamic acid amide levels and enhanced resistance to Pseudomonas syringae.

    Science.gov (United States)

    Campos, Laura; Lisón, Purificación; López-Gresa, María Pilar; Rodrigo, Ismael; Zacarés, Laura; Conejero, Vicente; Bellés, José María

    2014-10-01

    Hydroxycinnamic acid amides (HCAA) are secondary metabolites involved in plant development and defense that have been widely reported throughout the plant kingdom. These phenolics show antioxidant, antiviral, antibacterial, and antifungal activities. Hydroxycinnamoyl-CoA:tyramine N-hydroxycinnamoyl transferase (THT) is the key enzyme in HCAA synthesis and is induced in response to pathogen infection, wounding, or elicitor treatments, preceding HCAA accumulation. We have engineered transgenic tomato plants overexpressing tomato THT. These plants displayed an enhanced THT gene expression in leaves as compared with wild type (WT) plants. Consequently, leaves of THT-overexpressing plants showed a higher constitutive accumulation of the amide coumaroyltyramine (CT). Similar results were found in flowers and fruits. Moreover, feruloyltyramine (FT) also accumulated in these tissues, being present at higher levels in transgenic plants. Accumulation of CT, FT and octopamine, and noradrenaline HCAA in response to Pseudomonas syringae pv. tomato infection was higher in transgenic plants than in the WT plants. Transgenic plants showed an enhanced resistance to the bacterial infection. In addition, this HCAA accumulation was accompanied by an increase in salicylic acid levels and pathogenesis-related gene induction. Taken together, these results suggest that HCAA may play an important role in the defense of tomato plants against P. syringae infection.

  12. Soil water flow is a source of the plant pathogen Pseudomonas syringae in subalpine headwaters.

    Science.gov (United States)

    Monteil, Caroline L; Lafolie, François; Laurent, Jimmy; Clement, Jean-Christophe; Simler, Roland; Travi, Yves; Morris, Cindy E

    2014-07-01

    The airborne plant pathogenic bacterium Pseudomonas syringae is ubiquitous in headwaters, snowpack and precipitation where its populations are genetically and phenotypically diverse. Here, we assessed its population dynamics during snowmelt in headwaters of the French Alps. We revealed a continuous and significant transport of P.syringae by these waters in which the population density is correlated with water chemistry. Via in situ observations and laboratory experiments, we validated that P.syringae is effectively transported with the snow melt and rain water infiltrating through the soil of subalpine grasslands, leading to the same range of concentrations as measured in headwaters (10(2) -10(5) CFU l(-1) ). A population structure analysis confirmed the relatedness between populations in percolated water and those above the ground (i.e. rain, leaf litter and snowpack). However, the transport study in porous media suggested that water percolation could have different efficiencies for different strains of P.syringae. Finally, leaching of soil cores incubated for up to 4 months at 8°C showed that indigenous populations of P.syringae were able to survive in subalpine soil under cold temperature. This study brings to light the underestimated role of hydrological processes involved in the long distance dissemination of P.syringae. © 2013 Society for Applied Microbiology and John Wiley & Sons Ltd.

  13. Fungicidal activities and mechanisms of action of Pseudomonas syringae pv. syringae lipodepsipeptide syringopeptins 22A and 25A

    Directory of Open Access Journals (Sweden)

    Mekki F. Bensaci

    2011-10-01

    Full Text Available The plant-associated bacterium Pseudomonas syringae pv. syringae simultaneously produces two classes of metabolites: the small cyclic lipodepsinonapeptides such as the syringomycins and the larger cyclic lipodepsipeptide syringopeptins SP22 or SP25. The syringomycins inhibit a broad spectrum of fungi (but particularly yeasts by lipid-dependent membrane interaction. The syringopeptins are phytotoxic and inhibitory to Gram positive bacteria. In this study, the fungicidal activities of two major syringopeptins, SP22A and SP25A, and their mechanisms of action were investigated and compared to those of syringomycin E. SP22A and SP25A were observed to inhibit the fungal yeasts Saccharomyces cerevisiae and Candida albicans although less effectively than syringomycin E. S. cerevisiae mutants defective in ergosterol and sphingolipid biosyntheses were less susceptible to SP22A and SP25A but the relative inhibitory capabilities of SRE vs. SP22A and SP25A were maintained. Similar differences were observed for capabilities to cause cellular K+ and Ca2+ fluxes in S. cerevisiae. Interestingly, in phospholipid bilayers the syringopeptins are found to induce larger macroscopic ionic conductances than syringomycin E but form single channels with similar properties. These findings suggest that the syringopeptins target the yeast plasma membrane, and, like syringomycin E, employ a lipid-dependent channel forming mechanism of action. The differing degrees of growth inhibition by these lipodepsipeptides may be explained by differences in their hydrophobicity. The more hydrophobic SP22A and SP25A might interact more strongly with the yeast cell wall that would create a selective barrier for their incorporation into the plasma membrane.

  14. Resistant and susceptible responses in alfalfa (Medicago sativa to bacterial stem blight caused by Pseudomonas syringae pv. syringae.

    Directory of Open Access Journals (Sweden)

    Lev G Nemchinov

    Full Text Available Bacterial stem blight caused by Pseudomonas syringae pv. syringae is a common disease of alfalfa (Medicago sativa L. Little is known about host-pathogen interactions and host defense mechanisms. Here, individual resistant and susceptible plants were selected from cultivars Maverick and ZG9830 and used for transcript profiling at 24 and 72 hours after inoculation (hai with the isolate PssALF3. Bioinformatic analysis revealed a number of differentially expressed genes (DEGs in resistant and susceptible genotypes. Although resistant plants from each cultivar produced a hypersensitive response, transcriptome analyses indicated that they respond differently at the molecular level. The number of DEGs was higher in resistant plants of ZG9830 at 24 hai than in Maverick, suggesting that ZG9830 plants had a more rapid effector triggered immune response. Unique up-regulated genes in resistant ZG9830 plants included genes encoding putative nematode resistance HSPRO2-like proteins, orthologs for the rice Xa21 and soybean Rpg1-b resistance genes, and TIR-containing R genes lacking both NBS and LRR domains. The suite of R genes up-regulated in resistant Maverick plants had an over-representation of R genes in the CC-NBS-LRR family including two genes for atypical CCR domains and a putative ortholog of the Arabidopsis RPM1 gene. Resistance in both cultivars appears to be mediated primarily by WRKY family transcription factors and expression of genes involved in protein phosphorylation, regulation of transcription, defense response including synthesis of isoflavonoids, and oxidation-reduction processes. These results will further the identification of mechanisms involved in resistance to facilitate selection of parent populations and development of commercial varieties.

  15. Resistant and susceptible responses in alfalfa (Medicago sativa) to bacterial stem blight caused by Pseudomonas syringae pv. syringae.

    Science.gov (United States)

    Nemchinov, Lev G; Shao, Jonathan; Lee, Maya N; Postnikova, Olga A; Samac, Deborah A

    2017-01-01

    Bacterial stem blight caused by Pseudomonas syringae pv. syringae is a common disease of alfalfa (Medicago sativa L). Little is known about host-pathogen interactions and host defense mechanisms. Here, individual resistant and susceptible plants were selected from cultivars Maverick and ZG9830 and used for transcript profiling at 24 and 72 hours after inoculation (hai) with the isolate PssALF3. Bioinformatic analysis revealed a number of differentially expressed genes (DEGs) in resistant and susceptible genotypes. Although resistant plants from each cultivar produced a hypersensitive response, transcriptome analyses indicated that they respond differently at the molecular level. The number of DEGs was higher in resistant plants of ZG9830 at 24 hai than in Maverick, suggesting that ZG9830 plants had a more rapid effector triggered immune response. Unique up-regulated genes in resistant ZG9830 plants included genes encoding putative nematode resistance HSPRO2-like proteins, orthologs for the rice Xa21 and soybean Rpg1-b resistance genes, and TIR-containing R genes lacking both NBS and LRR domains. The suite of R genes up-regulated in resistant Maverick plants had an over-representation of R genes in the CC-NBS-LRR family including two genes for atypical CCR domains and a putative ortholog of the Arabidopsis RPM1 gene. Resistance in both cultivars appears to be mediated primarily by WRKY family transcription factors and expression of genes involved in protein phosphorylation, regulation of transcription, defense response including synthesis of isoflavonoids, and oxidation-reduction processes. These results will further the identification of mechanisms involved in resistance to facilitate selection of parent populations and development of commercial varieties.

  16. Pseudomonas syringae pv. tomato: the right pathogen, of the right plant, at the right time.

    Science.gov (United States)

    Preston, G M

    2000-09-01

    Abstract Pseudomonas syringae pv. tomato and the closely related pathovar P. s. pv. maculicola have been the focus of intensive research in recent years, not only because of the diseases they cause on tomato and crucifers, but because strains such as P. s. pv. tomato DC3000 and P. s. pv. maculicola ES4326 are pathogens of the model plant Arabidopsis thaliana. Consequently, both P. s. pv. tomato and P. s. pv. maculicola have been widely used to study the molecular mechanisms of host responses to infection. Analyses of the molecular basis of pathogenesis in P. s. pv. tomato reveal a complex and intimate interaction between bacteria and plant cells that depends on the coordinated expression of multiple pathogenicity and virulence factors. These include toxins, extracellular proteins and polysaccharides, and the translocation of proteins into plant cells by the type III (Hrp) secretion system. The contribution of individual virulence factors to parasitism and disease development varies significantly between strains. Application of functional genomics and cell biology to both pathogen and host within the P. s. pv. tomato/A. thaliana pathosystem provides a unique opportunity to unravel the molecular interactions underlying plant pathogenesis. Taxonomic relationship: Bacteria; Proteobacteria; gamma subdivision; Pseudomonadaceae/Moraxellaceae group; Pseudomonadaceae family; Pseudomonas genus; Pseudomonas syringae species; tomato pathovar. Microbiological properties: Gram-negative, aerobic, motile, rod-shaped, polar flagella, oxidase negative, arginine dihydrolase negative, DNA 58-60 mol% GC, elicits the hypersensitive response on tobacco. Primarily studied as the causal agent of bacterial speck of tomato and as a model pathogen of A. thaliana, although it has been isolated from a wide range of crop and weed species. Disease symptoms: Tomato (Lycopersicon esculentum): Brown-black leaf spots sometimes surrounded by chlorotic margin; dark superficial specks on green fruit

  17. Dynamics of defense responses and cell fate change during Arabidopsis-Pseudomonas syringae interactions.

    Directory of Open Access Journals (Sweden)

    Safae Hamdoun

    Full Text Available Plant-pathogen interactions involve sophisticated action and counteraction strategies from both parties. Plants can recognize pathogen derived molecules, such as conserved pathogen associated molecular patterns (PAMPs and effector proteins, and subsequently activate PAMP-triggered immunity (PTI and effector-triggered immunity (ETI, respectively. However, pathogens can evade such recognitions and suppress host immunity with effectors, causing effector-triggered susceptibility (ETS. The differences among PTI, ETS, and ETI have not been completely understood. Toward a better understanding of PTI, ETS, and ETI, we systematically examined various defense-related phenotypes of Arabidopsis infected with different Pseudomonas syringae pv. maculicola ES4326 strains, using the virulence strain DG3 to induce ETS, the avirulence strain DG34 that expresses avrRpm1 (recognized by the resistance protein RPM1 to induce ETI, and HrcC(- that lacks the type three secretion system to activate PTI. We found that plants infected with different strains displayed dynamic differences in the accumulation of the defense signaling molecule salicylic acid, expression of the defense marker gene PR1, cell death formation, and accumulation/localization of the reactive oxygen species, H2O2. The differences between PTI, ETS, and ETI are dependent on the doses of the strains used. These data support the quantitative nature of PTI, ETS, and ETI and they also reveal qualitative differences between PTI, ETS, and ETI. Interestingly, we observed the induction of large cells in the infected leaves, most obviously with HrcC(- at later infection stages. The enlarged cells have increased DNA content, suggesting a possible activation of endoreplication. Consistent with strong induction of abnormal cell growth by HrcC(-, we found that the PTI elicitor flg22 also activates abnormal cell growth, depending on a functional flg22-receptor FLS2. Thus, our study has revealed a comprehensive

  18. Defence responses of arabidopsis thaliana to infection by pseudomonas syringae are regulated by the circadian clock

    KAUST Repository

    Bhardwaj, Vaibhav

    2011-10-31

    The circadian clock allows plants to anticipate predictable daily changes in abiotic stimuli, such as light; however, whether the clock similarly allows plants to anticipate interactions with other organisms is unknown. Here we show that Arabidopsis thaliana (Arabidopsis) has circadian clock-mediated variation in resistance to the virulent bacterial pathogen Pseudomonas syringae pv. tomato DC3000 (Pst DC3000), with plants being least susceptible to infection in the subjective morning. We suggest that the increased resistance to Pst DC3000 observed in the morning in Col-0 plants results from clock-mediated modulation of pathogen associated molecular pattern (PAMP)-triggered immunity. Analysis of publicly available microarray data revealed that a large number of Arabidopsis defence-related genes showed both diurnal- and circadian-regulation, including genes involved in the perception of the PAMP flagellin which exhibit a peak in expression in the morning. Accordingly, we observed that PAMP-triggered callose deposition was significantly higher in wild-type plants inoculated with Pst DC3000 hrpA in the subjective morning than in the evening, while no such temporal difference was evident in arrhythmic plants. Our results suggest that PAMP-triggered immune responses are modulated by the circadian clock and that temporal regulation allows plants to anticipate and respond more effectively to pathogen challenges in the daytime. © 2011 Bhardwaj et al.

  19. Pseudomonas syringae Catalases Are Collectively Required for Plant Pathogenesis

    Science.gov (United States)

    Guo, Ming; Block, Anna; Bryan, Crystal D.; Becker, Donald F.

    2012-01-01

    The bacterial pathogen Pseudomonas syringae pv. tomato DC3000 must detoxify plant-produced hydrogen peroxide (H2O2) in order to survive in its host plant. Candidate enzymes for this detoxification include the monofunctional catalases KatB and KatE and the bifunctional catalase-peroxidase KatG of DC3000. This study shows that KatG is the major housekeeping catalase of DC3000 and provides protection against menadione-generated endogenous H2O2. In contrast, KatB rapidly and substantially accumulates in response to exogenous H2O2. Furthermore, KatB and KatG have nonredundant roles in detoxifying exogenous H2O2 and are required for full virulence of DC3000 in Arabidopsis thaliana. Therefore, the nonredundant ability of KatB and KatG to detoxify plant-produced H2O2 is essential for the bacteria to survive in plants. Indeed, a DC3000 catalase triple mutant is severely compromised in its ability to grow in planta, and its growth can be partially rescued by the expression of katB, katE, or katG. Interestingly, our data demonstrate that although KatB and KatG are the major catalases involved in the virulence of DC3000, KatE can also provide some protection in planta. Thus, our results indicate that these catalases are virulence factors for DC3000 and are collectively required for pathogenesis. PMID:22797762

  20. The Facultative Symbiont Rickettsia Protects an Invasive Whitefly against Entomopathogenic Pseudomonas syringae Strains

    Science.gov (United States)

    Hunter, Martha S.; Baltrus, David A.

    2014-01-01

    Facultative endosymbionts can benefit insect hosts in a variety of ways, including context-dependent roles, such as providing defense against pathogens. The role of some symbionts in defense may be overlooked, however, when pathogen infection is transient, sporadic, or asymptomatic. The facultative endosymbiont Rickettsia increases the fitness of the sweet potato whitefly (Bemisia tabaci) in some populations through mechanisms that are not yet understood. In this study, we investigated the role of Rickettsia in mediating the interaction between the sweet potato whitefly and Pseudomonas syringae, a common environmental bacterium, some strains of which are pathogenic to aphids. Our results show that P. syringae multiplies within whiteflies, leading to host death, and that whiteflies infected with Rickettsia show a decreased rate of death due to P. syringae. Experiments using plants coated with P. syringae confirmed that whiteflies can acquire the bacteria at a low rate while feeding, leading to increased mortality, particularly when the whiteflies are not infected with Rickettsia. These results suggest that P. syringae may affect whitefly populations in nature and that Rickettsia can ameliorate this effect. This study highlights the possible importance of interactions among opportunistic environmental pathogens and endosymbionts of insects. PMID:25217020

  1. The mbo operon is specific and essential for biosynthesis of mangotoxin in Pseudomonas syringae.

    Science.gov (United States)

    Carrión, Víctor J; Arrebola, Eva; Cazorla, Francisco M; Murillo, Jesús; de Vicente, Antonio

    2012-01-01

    Mangotoxin is an antimetabolite toxin produced by certain Pseudomonas syringae pv. syringae strains. This toxin is an oligopeptide that inhibits ornithine N-acetyl transferase, a key enzyme in the biosynthesis of ornithine and arginine. Previous studies have reported the involvement of the putative nonribosomal peptide synthetase MgoA in virulence and mangotoxin production. In this study, we analyse a new chromosomal region of P. syringae pv. syringae UMAF0158, which contains six coding sequences arranged as an operon (mbo operon). The mbo operon was detected in only mangotoxin-producing strains, and it was shown to be essential for the biosynthesis of this toxin. Mutants in each of the six ORFs of the mbo operon were partially or completely impaired in the production of the toxin. In addition, Pseudomonas spp. mangotoxin non-producer strains transformed with the mbo operon gained the ability to produce mangotoxin, indicating that this operon contains all the genetic information necessary for mangotoxin biosynthesis. The generation of a single transcript for the mbo operon was confirmed and supported by the allocation of a unique promoter and Rho-independent terminator. The phylogenetic analysis of the P. syringae strains harbouring the mbo operon revealed that these strains clustered together.

  2. Pseudomonas syringae enhances herbivory by suppressing the reactive oxygen burst in Arabidopsis.

    Science.gov (United States)

    Groen, Simon C; Humphrey, Parris T; Chevasco, Daniela; Ausubel, Frederick M; Pierce, Naomi E; Whiteman, Noah K

    2016-01-01

    Plant-herbivore interactions have evolved in the presence of plant-colonizing microbes. These microbes can have important third-party effects on herbivore ecology, as exemplified by drosophilid flies that evolved from ancestors feeding on plant-associated microbes. Leaf-mining flies in the genus Scaptomyza, which is nested within the paraphyletic genus Drosophila, show strong associations with bacteria in the genus Pseudomonas, including Pseudomonas syringae. Adult females are capable of vectoring these bacteria between plants and larvae show a preference for feeding on P. syringae-infected leaves. Here we show that Scaptomyza flava larvae can also vector P. syringae to and from feeding sites, and that they not only feed more, but also develop faster on plants previously infected with P. syringae. Our genetic and physiological data show that P. syringae enhances S. flava feeding on infected plants at least in part by suppressing anti-herbivore defenses mediated by reactive oxygen species. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Genome Sequences of Two Pseudomonas syringae pv. tomato Race 1 Strains, Isolated from Tomato Fields in California

    OpenAIRE

    Thapa, Shree P.; Coaker, Gitta

    2016-01-01

    Pseudomonas syringae pv. tomato race 1 strains have evolved to overcome genetic resistance in tomato. Here, we present the draft genome sequences of two race 1 P.?syringae pv. tomato strains, A9 and 407, isolated from diseased tomato plants in California.

  4. 40 CFR 180.1114 - Pseudomonas fluorescens A506, Pseudomonas fluorescens 1629RS, and Pseudomonas syringae 742RS...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Pseudomonas fluorescens A506, Pseudomonas fluorescens 1629RS, and Pseudomonas syringae 742RS; exemptions from the requirement of a tolerance... Tolerances § 180.1114 Pseudomonas fluorescens A506, Pseudomonas fluorescens 1629RS, and Pseudomonas syringae...

  5. Bacterial canker of plum caused by Pseudomonas syringae pathovars, as a serious threat for plum production in the Netherlands

    NARCIS (Netherlands)

    Wenneker, M.; Janse, J.D.; Bruine, de A.; Vink, P.; Pham, K.T.K.

    2012-01-01

    In the Netherlands, bacterial canker of plum trees (Prunus domestica) caused by Pseudomonas syringae pathovars syringae and morsprunorum is a recent and serious problem. The trunks of the affected plum trees are girdled by cankers resulting in relatively sudden death of the trees 1 to 4 years after

  6. Constitutive Activity of the Arabidopsis MAP Kinase 3 Confers Resistance to Pseudomonas syringae and Drives Robust Immune Responses

    KAUST Repository

    Lang, Julien

    2017-08-02

    Mitogen Activated Protein Kinases (MAPKs) are known to be important mediators of plant responses to biotic and abiotic stresses. In a recent report, we enlarged the understanding of the Arabidopsis thaliana MPK3 functions showing that the expression of a constitutively active (CA) form of the protein led to auto-immune phenotypes. CA-MPK3 plants are dwarf and display defense responses that are characterized by the accumulation of salicylic acid and phytoalexins as well as by the upregulation of several defense genes. Consistently with these data, we present here results demonstrating that, compared to wild type controls, CA-MPK3 plants are more resistant to the hemibiotrophic pathogen Pseudomonas syringae DC3000. Based on our previous work, we also discuss the mechanisms of robust plant immunity controlled by sustained MPK3 activity, focusing especially on the roles of disease resistance proteins.

  7. Substrate and target sequence length influence RecTE(Psy recombineering efficiency in Pseudomonas syringae.

    Directory of Open Access Journals (Sweden)

    Zhongmeng Bao

    Full Text Available We are developing a new recombineering system to assist experimental manipulation of the Pseudomonas syringae genome. P. syringae is a globally dispersed plant pathogen and an important model species used to study the molecular biology of bacteria-plant interactions. We previously identified orthologs of the lambda Red bet/exo and Rac recET genes in P. syringae and confirmed that they function in recombineering using ssDNA and dsDNA substrates. Here we investigate the properties of dsDNA substrates more closely to determine how they influence recombineering efficiency. We find that the length of flanking homologies and length of the sequences being inserted or deleted have a large effect on RecTE(Psy mediated recombination efficiency. These results provide information about the design elements that should be considered when using recombineering.

  8. Bigger is not always better: transmission and fitness burden of ∼1MB Pseudomonas syringae megaplasmid pMPPla107.

    Science.gov (United States)

    Romanchuk, Artur; Jones, Corbin D; Karkare, Kedar; Moore, Autumn; Smith, Brian A; Jones, Chelsea; Dougherty, Kevin; Baltrus, David A

    2014-05-01

    Horizontal gene transfer (HGT) is a widespread process that enables the acquisition of genes and metabolic pathways in single evolutionary steps. Previous reports have described fitness costs of HGT, but have largely focused on the acquisition of relatively small plasmids. We have previously shown that a Pseudomonas syringae pv. lachrymans strain recently acquired a cryptic megaplasmid, pMPPla107. This extrachromosomal element contributes hundreds of new genes to P. syringae and increases total genomic content by approximately 18%. However, this early work did not directly explore transmissibility, stability, or fitness costs associated with acquisition of pMPPla107. Here, we show that pMPPla107 is self-transmissible across a variety of diverse pseudomonad strains, on both solid agar and within shaking liquid cultures, with conjugation dependent on a type IV secretion system. To the best of our knowledge, this is the largest self-transmissible megaplasmid known outside of Sinorhizobium. This megaplasmid can be lost from all novel hosts although the rate of loss depends on medium type and genomic background. However, in contrast, pMPPla107 is faithfully maintained within the original parent strain (Pla107) even under direct negative selection during laboratory assays. These results suggest that Pla107 specific stabilizing mutations have occurred either on this strain's chromosome or within the megaplasmid. Lastly, we demonstrate that acquisition of pMPPla107 by strains other than Pla107 imparts severe (20%) fitness costs under competitive conditions in vitro. We show that pMPPla107 is capable of transmitting and maintaining itself across multiple Pseudomonas species, rendering it one of the largest conjugative elements discovered to date. The relative stability of pMPPla107, coupled with extensive fitness costs, makes it a tractable model system for investigating evolutionary and genetic mechanisms of megaplasmid maintenance and a unique testing ground to explore

  9. Construction of a tomato leaf cDNA expression library and immunoscreening for the Pseudomonas syringae pv. tomato DC3000 HrpZ1 target protein

    OpenAIRE

    Österman, Janina

    2009-01-01

    Pseudomonas syringae pv. tomato DC3000 is a Gram-negative plant pathogen that causes bacterial speck disease on tomato. The virulence of this bacterium is based on the type III secretion system (T3SS). Similar systems are also used by many other plant and animal pathogens, as well as symbiotic bacteria. The T3SS enables the transfer of specific bacterial virulence proteins from the bacterial cytoplasm into the host cell. This secretion is mediated by a needle-like structure that penetrates th...

  10. Pseudomonas syringae evades host immunity by degrading flagellin monomers with alkaline protease AprA.

    Science.gov (United States)

    Pel, Michiel J C; van Dijken, Anja J H; Bardoel, Bart W; Seidl, Michael F; van der Ent, Sjoerd; van Strijp, Jos A G; Pieterse, Corné M J

    2014-07-01

    Bacterial flagellin molecules are strong inducers of innate immune responses in both mammals and plants. The opportunistic pathogen Pseudomonas aeruginosa secretes an alkaline protease called AprA that degrades flagellin monomers. Here, we show that AprA is widespread among a wide variety of bacterial species. In addition, we investigated the role of AprA in virulence of the bacterial plant pathogen P. syringae pv. tomato DC3000. The AprA-deficient DC3000 ΔaprA knockout mutant was significantly less virulent on both tomato and Arabidopsis thaliana. Moreover, infiltration of A. thaliana Col-0 leaves with DC3000 ΔaprA evoked a significantly higher level of expression of the defense-related genes FRK1 and PR-1 than did wild-type DC3000. In the flagellin receptor mutant fls2, pathogen virulence and defense-related gene activation did not differ between DC3000 and DC3000 ΔaprA. Together, these results suggest that AprA of DC3000 is important for evasion of recognition by the FLS2 receptor, allowing wild-type DC3000 to be more virulent on its host plant than AprA-deficient DC3000 ΔaprA. To provide further evidence for the role of DC3000 AprA in host immune evasion, we overexpressed the AprA inhibitory peptide AprI of DC3000 in A. thaliana to counteract the immune evasive capacity of DC3000 AprA. Ectopic expression of aprI in A. thaliana resulted in an enhanced level of resistance against wild-type DC3000, while the already elevated level of resistance against DC3000 ΔaprA remained unchanged. Together, these results indicate that evasion of host immunity by the alkaline protease AprA is important for full virulence of strain DC3000 and likely acts by preventing flagellin monomers from being recognized by its cognate immune receptor.

  11. Genomic Distribution and Divergence of Levansucrase-Coding Genes in Pseudomonas syringae

    Directory of Open Access Journals (Sweden)

    Matthias S. Ullrich

    2012-02-01

    Full Text Available In the plant pathogenic bacterium, Pseudomonas syringae, the exopolysaccharide levan is synthesized by extracellular levansucrase (Lsc, which is encoded by two conserved 1,296-bp genes termed lscB and lscC in P. syringae strain PG4180. A third gene, lscA, is homologous to the 1,248-bp lsc gene of the bacterium Erwinia amylovora, causing fire blight. However, lscA is not expressed in P. syringae strain PG4180. Herein, PG4180 lscA was shown to be expressed from its native promoter in the Lsc-deficient E. amylovora mutant, Ea7/74-LS6, suggesting that lscA might be closely related to the E. amylovora lsc gene. Nucleotide sequence analysis revealed that lscB and lscC homologs in several P. syringae strains are part of a highly conserved 1.8-kb region containing the ORF, flanked by 450-452-bp and 49-51-bp up- and downstream sequences, respectively. Interestingly, the 450-452-bp upstream sequence, along with the initial 48-bp ORF sequence encoding for the N-terminal 16 amino acid residues of Lsc, were found to be highly similar to the respective sequence of a putatively prophage-borne glycosyl hydrolase-encoding gene in several P. syringae genomes. Minimal promoter regions of lscB and lscC were mapped in PG4180 by deletion analysis and were found to be located in similar positions upstream of lsc genes in three P. syringae genomes. Thus, a putative 498-500-bp promoter element was identified, which possesses the prophage-associated com gene and DNA encoding common N-terminal sequences of all 1,296-bp Lsc and two glycosyl hydrolases. Since the gene product of the non-expressed 1,248-bp lscA is lacking this conserved N-terminal region but is otherwise highly homologous to those of lscB and lscC, it was concluded that lscA might have been the ancestral lsc gene in E. amylovora and P. syringae. Our data indicated that its highly expressed paralogs in P. syringae are probably derived from subsequent recombination events initiated by insertion of the 498

  12. The mangotoxin biosynthetic operon (mbo) is specifically distributed within Pseudomonas syringae genomospecies 1 and was acquired only once during evolution.

    Science.gov (United States)

    Carrión, Víctor J; Gutiérrez-Barranquero, José A; Arrebola, Eva; Bardaji, Leire; Codina, Juan C; de Vicente, Antonio; Cazorla, Francisco M; Murillo, Jesús

    2013-02-01

    Mangotoxin production was first described in Pseudomonas syringae pv. syringae strains. A phenotypic characterization of 94 P. syringae strains was carried out to determine the genetic evolution of the mangotoxin biosynthetic operon (mbo). We designed a PCR primer pair specific for the mbo operon to examine its distribution within the P. syringae complex. These primers amplified a 692-bp DNA fragment from 52 mangotoxin-producing strains and from 7 non-mangotoxin-producing strains that harbor the mbo operon, whereas 35 non-mangotoxin-producing strains did not yield any amplification. This, together with the analysis of draft genomes, allowed the identification of the mbo operon in five pathovars (pathovars aptata, avellanae, japonica, pisi, and syringae), all of which belong to genomospecies 1, suggesting a limited distribution of the mbo genes in the P. syringae complex. Phylogenetic analyses using partial sequences from housekeeping genes differentiated three groups within genomospecies 1. All of the strains containing the mbo operon clustered in groups I and II, whereas those lacking the operon clustered in group III; however, the relative branching order of these three groups is dependent on the genes used to construct the phylogeny. The mbo operon maintains synteny and is inserted in the same genomic location, with high sequence conservation around the insertion point, for all the strains in groups I and II. These data support the idea that the mbo operon was acquired horizontally and only once by the ancestor of groups I and II from genomospecies 1 within the P. syringae complex.

  13. BOX-PCR-based identification of bacterial species belonging to Pseudomonas syringae: P. viridiflava group

    Directory of Open Access Journals (Sweden)

    Abi S.A. Marques

    2008-01-01

    Full Text Available The phenotypic characteristics and genetic fingerprints of a collection of 120 bacterial strains, belonging to Pseudomonas syringae sensu lato group, P. viridiflava and reference bacteria were evaluated, with the aim of species identification. The numerical analysis of 119 nutritional characteristics did not show patterns that would help with identification. Regarding the genetic fingerprinting, the results of the present study supported the observation that BOX-PCR seems to be able to identify bacterial strains at species level. After numerical analyses of the bar-codes, all pathovars belonging to each one of the nine described genomospecies were clustered together at a distance of 0.72, and could be separated at genomic species level. Two P. syringae strains of unknown pathovars (CFBP 3650 and CFBP 3662 and the three P. syringae pv. actinidiae strains were grouped in two extra clusters and might eventually constitute two new species. This genomic species clustering was particularly evident for genomospecies 4, which gathered P. syringae pvs. atropurpurea, coronafaciens, garçae, oryzae, porri, striafaciens, and zizaniae at a noticeably low distance.

  14. Syringa oblata Lindl var. alba as a source of oleuropein and related compounds

    NARCIS (Netherlands)

    Nenadis, N.; Vervoort, J.J.M.; Boeren, J.A.; Tsimidou, M.Z.

    2007-01-01

    The leaf methanol extract of Syringa oblata Lindl var. alba was investigated as a source of oleuropein and related compounds. The extract had a high total phenol content and a radical scavenging activity similar to that of the respective extract from Olea europaea leaves. HPLC-DAD characterisation

  15. A Mathematical model to investigate quorum sensing regulation and its heterogenecity in pseudomonas syringae on leaves

    Science.gov (United States)

    The bacterium Pseudomonas syringae is a plant-pathogen, which through quorum sensing (QS), controls virulence. In this paper, by means of mathematical modeling, we investigate QS of this bacterium when living on leaf surfaces. We extend an existing stochastic model for the formation of Pseudomonas s...

  16. Dynamics of sugar content in vegetative organs of Syringa Genus representatives introduced into Steppe Zone

    Directory of Open Access Journals (Sweden)

    L. G. Dolgova

    2005-12-01

    Full Text Available Quantitative and qualitative contents of sugars in phases of growth and development in overground organs of species of Syringa L. genus were determined. It is shown a cryoprotective role of sugars in plants. Conclusions on resistance of plants under conditions of a steppe zone are made.

  17. Differential secretome analysis of Pseudomonas syringae pv tomato using gel-free MS proteomics

    Directory of Open Access Journals (Sweden)

    Jörg eSchumacher

    2014-07-01

    Full Text Available The plant pathogen Pseudomonas syringae pv. tomato (DC3000 causes virulence by delivering effector proteins into host plant cells through its type three secretion system (T3SS. In response to the plant environment DC3000 expresses hypersensitive response and pathogenicity genes (hrp. Pathogenesis depends on the ability of the pathogen to manipulate the plant metabolism and to inhibit plant immunity, which depends to a large degree on the plant’s capacity to recognise both pathogen and microbial determinants (PAMP/MAMP-triggered immunity. We have developed and employed MS-based shotgun and targeted proteomics to (i elucidate the extracellular and secretome composition of DC3000 and (ii evaluate temporal features of the assembly of the T3SS and the secretion process together with its dependence of pH. The proteomic screen, under hrp inducing in vitro conditions, of extracellular and cytoplasmatic fractions indicated the segregated presence of not only T3SS implicated proteins such as HopK1, HrpK1, HrpA1 and Avrpto1, but also of proteins not usually associated with the T3SS or with pathogenicity. Using multiple reaction monitoring MS (MRM-MS to quantify HrpA1 and Avrpto1, we found that HrpA1 is rapidly expressed, at a strict pH-dependent rate and is post-translationally processed extracellularly. These features appear to not interfere with rapid Avrpto1 expression and secretion but may suggest some temporal post-translational regulatory mechanism of the T3SS assembly. The high specificity and sensitivity of the MRM-MS approach should provide a powerful tool to measure secretion and translocation in infected tissues.

  18. Eggplant and related species are promising genetic resources to dissect the plant immune response to Pseudomonas syringae and Xanthomonas euvesicatoria and to identify new resistance determinants.

    Science.gov (United States)

    Clarke, Christopher R; Hayes, Byron W; Runde, Brendan J; Wicker, Emmanuel; Vinatzer, Boris A

    2014-10-01

    The apparent lack of durability of many resistance (R) genes highlights the need for the constant identification of new genetic sources of resistance for the breeding of new disease-resistant crop cultivars. To this end, we screened a collection of accessions of eggplant and close relatives for resistance against Pseudomonas syringae pv. tomato (Pto) and Xanthomonas euvesicatoria (Xeu), foliar plant pathogens of many solanaceous crops. Both pathogens caused substantial disease on most genotypes of eggplant and its relatives. Promisingly, however, some of the genotypes were fully or partially resistant to either of the pathogens, suggesting the presence of effective resistance determinants in these genotypes. Segregation of resistance to the growth of Xeu following infiltration in F2 progeny from a cross of a resistant and susceptible genotype suggests that resistance to Xeu is inherited as a multigenic trait. With regard to Pto, a mutant strain lacking all 28 functional type III secreted effectors, and a Pseudomonas fluorescens strain expressing a P. syringae type III secretion system (T3SS), both elicit a strong cell death response on most eggplant lines. Several genotypes thus appear to harbour a mechanism for the direct recognition of a component of the T3SS. Therefore, eggplant and its close relatives are promising resources to unravel novel aspects of plant immunity and to identify new candidate R genes that could be employed in other Solanaceae in which Xeu and Pto cause agriculturally relevant diseases. © 2014 BSPP AND JOHN WILEY & SONS LTD.

  19. Constitutive activation of jasmonate signaling in an Arabidopsis mutant correlates with enhanced resistance to Erysiphe cichoracearum, Pseudomonas syringae, and Myzus persicae.

    Science.gov (United States)

    Ellis, Christine; Karafyllidis, Ioannis; Turner, John G

    2002-10-01

    In Arabidopsis spp., the jasmonate (JA) response pathway generally is required for defenses against necrotrophic pathogens and chewing insects, while the salicylic acid (SA) response pathway is generally required for specific, resistance (R) gene-mediated defenses against both biotrophic and necrotrophic pathogens. For example, SA-dependent defenses are required for resistance to the biotrophic fungal pathogen Erysiphe cichoracearum UCSC1 and the bacterial pathogen Pseudomonas syringae pv. maculicola, and also are expressed during response to the green peach aphid Myzus persicae. However, recent evidence indicates that the expression of JA-dependent defenses also may confer resistance to E. cichoracearum. To confirm and to extend this observation, we have compared the disease and pest resistance of wild-type Arabidopsis plants with that of the mutants coil, which is insensitive to JA, and cev1, which has constitutive JA signaling. Measurements of the colonization of these plants by E. cichoracearum, P. syringae pv. maculicola, and M. persicae indicated that activation of the JA signal pathway enhanced resistance, and was associated with the activation of JA-dependent defense genes and the suppression of SA-dependent defense genes. We conclude that JA and SA induce alternative defense pathways that can confer resistance to the same pathogens and pests.

  20. The life history of Pseudomonas syringae: linking agriculture to earth system processes.

    Science.gov (United States)

    Morris, Cindy E; Monteil, Caroline L; Berge, Odile

    2013-01-01

    The description of the ecology of Pseudomonas syringae is moving away from that of a ubiquitous epiphytic plant pathogen to one of a multifaceted bacterium sans frontières in fresh water and other ecosystems linked to the water cycle. Discovery of the aquatic facet of its ecology has led to a vision of its life history that integrates spatial and temporal scales spanning billions of years and traversing catchment basins, continents, and the planet and that confronts the implication of roles that are potentially conflicting for agriculture (as a plant pathogen and as an actor in processes leading to rain and snowfall). This new ecological perspective has also yielded insight into epidemiological phenomena linked to disease emergence. Overall, it sets the stage for the integration of more comprehensive contexts of ecology and evolutionary history into comparative genomic analyses to elucidate how P. syringae subverts the attack and defense responses of the cohabitants of the diverse environments it occupies.

  1. Transposon insertion libraries for the characterization of mutants from the kiwifruit pathogen Pseudomonas syringae pv. actinidiae

    Science.gov (United States)

    Mesarich, Carl H.; Rees-George, Jonathan; Gardner, Paul P.; Ghomi, Fatemeh Ashari; Gerth, Monica L.; Andersen, Mark T.; Rikkerink, Erik H. A.; Fineran, Peter C.

    2017-01-01

    Pseudomonas syringae pv. actinidiae (Psa), the causal agent of kiwifruit canker, is one of the most devastating plant diseases of recent times. We have generated two mini-Tn5-based random insertion libraries of Psa ICMP 18884. The first, a ‘phenotype of interest’ (POI) library, consists of 10,368 independent mutants gridded into 96-well plates. By replica plating onto selective media, the POI library was successfully screened for auxotrophic and motility mutants. Lipopolysaccharide (LPS) biosynthesis mutants with ‘Fuzzy-Spreader’-like morphologies were also identified through a visual screen. The second, a ‘mutant of interest’ (MOI) library, comprises around 96,000 independent mutants, also stored in 96-well plates, with approximately 200 individuals per well. The MOI library was sequenced on the Illumina MiSeq platform using Transposon-Directed Insertion site Sequencing (TraDIS) to map insertion sites onto the Psa genome. A grid-based PCR method was developed to recover individual mutants, and using this strategy, the MOI library was successfully screened for a putative LPS mutant not identified in the visual screen. The Psa chromosome and plasmid had 24,031 and 1,236 independent insertion events respectively, giving insertion frequencies of 3.65 and 16.6 per kb respectively. These data suggest that the MOI library is near saturation, with the theoretical probability of finding an insert in any one chromosomal gene estimated to be 97.5%. However, only 47% of chromosomal genes had insertions. This surprisingly low rate cannot be solely explained by the lack of insertions in essential genes, which would be expected to be around 5%. Strikingly, many accessory genes, including most of those encoding type III effectors, lacked insertions. In contrast, 94% of genes on the Psa plasmid had insertions, including for example, the type III effector HopAU1. These results suggest that some chromosomal sites are rendered inaccessible to transposon insertion, either

  2. CBL-interacting protein kinase 6 negatively regulates immune response to Pseudomonas syringae in Arabidopsis.

    Science.gov (United States)

    Sardar, Atish; Nandi, Ashis Kumar; Chattopadhyay, Debasis

    2017-06-15

    Cytosolic calcium ion (Ca2+) is an essential mediator of the plant innate immune response. Here, we report that a calcium-regulated protein kinase Calcineurin B-like protein (CBL)-interacting protein kinase 6 (CIPK6) functions as a negative regulator of immunity against the bacterial pathogen Pseudomonas syringae in Arabidopsis thaliana. Arabidopsis lines with compromised expression of CIPK6 exhibited enhanced disease resistance to the bacterial pathogen and to P. syringae harboring certain but not all avirulent effectors, while restoration of CIPK6 expression resulted in abolition of resistance. Plants overexpressing CIPK6 were more susceptible to P. syringae. Enhanced resistance in the absence of CIPK6 was accompanied by increased accumulation of salicylic acid and elevated expression of defense marker genes. Salicylic acid accumulation was essential for improved immunity in the absence of CIPK6. CIPK6 negatively regulated the oxidative burst associated with perception of pathogen-associated microbial patterns (PAMPs) and bacterial effectors. Accelerated and enhanced activation of the mitogen-activated protein kinase cascade in response to bacterial and fungal elicitors was observed in the absence of CIPK6. The results of this study suggested that CIPK6 negatively regulates effector-triggered and PAMP-triggered immunity in Arabidopsis. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  3. Survival and electrotransformation of Pseudomonas syringae strains under simulated cloud-like conditions.

    Science.gov (United States)

    Blanchard, Laurine S; Monin, Anaïs; Ouertani, Hounaïda; Touaibia, Lamia; Michel, Elisa; Buret, François; Simonet, Pascal; Morris, Cindy E; Demanèche, Sandrine

    2017-05-01

    To diversify their genetic material, and thereby allow adaptation to environmental disturbances and colonization of new ecological niches, bacteria use various evolutionary processes, including the acquisition of new genetic material by horizontal transfer mechanisms such as conjugation, transduction and transformation. Electrotransformation mediated by lightning-related electrical phenomena may constitute an additional gene-transfer mechanism occurring in nature. The presence in clouds of bacteria such as Pseudomonas syringae capable of forming ice nuclei that lead to precipitation, and that are likely to be involved in triggering lightning, led us to postulate that natural electrotransformation in clouds may contribute to the adaptive potential of these bacteria. Here, we quantify the survival rate of 10 P. syringae strains in liquid and icy media under such electrical pulses and their capacity to acquire exogenous DNA. In comparison to two other bacteria (Pseudomonas sp. N3 and Escherichia coli TOP10), P. syringae CC0094 appears to be best adapted for survival and for genetic electrotransformation under these conditions, which suggests that this bacterium would be able to survive and to get a boost in its adaptive potential while being transported in clouds and falling back to Earth with precipitation from storms. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  4. Vitamin B6 contributes to disease resistance against Pseudomonas syringae pv. tomato DC3000 and Botrytis cinerea in Arabidopsis thaliana.

    Science.gov (United States)

    Zhang, Yafen; Jin, Xiaoyi; Ouyang, Zhigang; Li, Xiaohui; Liu, Bo; Huang, Lei; Hong, Yongbo; Zhang, Huijuan; Song, Fengming; Li, Dayong

    2015-03-01

    Vitamin B6 (VB6) is an important cofactor for numerous enzymatic reactions and plays an important role in abiotic stress tolerance. However, direct molecular evidence supporting a role for VB6 in plant disease resistance remains lacking. In this study, we explored the possible function of VB6 in disease resistance by analyzing disease phenotypes of Arabidopsis mutants with defects in de novo biosynthetic pathway and salvage pathway of VB6 biosynthesis against Pseudomonas syringae pv. tomato (Pst) DC3000 and Botrytis cinerea. Mutations in AtPDX1.2 and AtPDX1.3 genes involved in the de novo pathway, and in AtSOS4 gene involved in the salvage pathway led to increased levels of diseases caused by Pst DC3000 and B. cinerea. The pdx1.2 and pdx1.3 plants had reduced VB6 contents and showed a further reduction in VB6 contents after infection by Pst DC3000 or B. cinerea. Our preliminary results suggest an important role for VB6 in plant disease resistance against different types of pathogens. Copyright © 2014 Elsevier GmbH. All rights reserved.

  5. Inhibitory effect of Thymus vulgaris and Origanum vulgare essential oils on virulence factors of phytopathogenic Pseudomonas syringae strains.

    Science.gov (United States)

    Carezzano, M E; Sotelo, J P; Primo, E; Reinoso, E B; Paletti Rovey, M F; Demo, M S; Giordano, W F; Oliva, M de Las M

    2017-07-01

    Pseudomonas syringae is a phytopathogenic bacterium that causes lesions in leaves during the colonisation process. The damage is associated with production of many virulence factors, such as biofilm and phytotoxins. The essential oils of Thymus vulgaris (thyme) and Origanum vulgare (oregano) have been demonstrated to inhibit P. syringae. The aim of this study was to investigate the effects of T. vulgaris and O. vulgare essential oils on production of virulence factors of phytopathogenic P. syringae strains, including anti-biofilm and anti-toxins activities. The broth microdilution method was used for determination of MIC and biofilm inhibition assays. Coronatine, syringomycin and tabtoxin were pheno- and genotypically evaluated. Both oils showed good inhibitory activity against P. syringae, with MIC values from 1.43 to 11.5 mg·ml -1 for thyme and 5.8 to 11.6 mg·ml -1 for oregano. Biofilm formation, production of coronatine, syringomycin and tabtoxin were inhibited by thyme and oregano essential oil in most strains. The results presented here are promising, demonstrating the bactericidal activity and reduction of virulence factor production after treatment with thyme and oregano oil, providing insight into how they exert their antibacterial activity. These natural products could be considered in the future for the control of diseases caused by P. syringae. © 2017 German Botanical Society and The Royal Botanical Society of the Netherlands.

  6. Overexpression of SAMDC1 gene in Arabidopsis thaliana increases expression of defense-related genes as well as resistance to Pseudomonas syringae and Hyaloperonospora arabidopsidis

    Directory of Open Access Journals (Sweden)

    Francisco eMarco

    2014-03-01

    Full Text Available It has been previously described that elevation of endogenous spermine levels in Arabidopsis could be achieved by transgenic overexpression of S-Adenosylmethionine decarboxylase (SAMDC or Spermine synthase (SPMS. In both cases, spermine accumulation had an impact on the plant transcriptome, with up-regulation of a set of genes enriched in functional categories involved in defense-related processes against both biotic and abiotic stresses. In this work, the response of SAMDC1-overexpressing plants against bacterial and oomycete pathogens has been tested. The expression of several pathogen defense-related genes was induced in these plants as well as in wild type plants exposed to an exogenous supply of spermine. SAMDC1-overexpressing plants showed an increased tolerance to infection by Pseudomonas syringae and by Hyaloperonospora arabidopsidis. Both results add more evidence to the hypothesis that spermine plays a key role in plant resistance to biotic stress.

  7. Pathovars of Pseudomonas syringae Causing Bacterial Brown Spot and Halo Blight in Phaseolus vulgaris L. Are Distinguishable by Ribotyping

    Science.gov (United States)

    González, Ana J.; Landeras, Elena; Mendoza, M. Carmen

    2000-01-01

    Ribotyping was evaluated as a method to differentiate between Pseudomonas syringae pv. phaseolicola and pv. syringae strains causing bacterial brown spot and halo blight diseases in Phaseolus vulgaris L. Ribotyping, with restriction enzymes BglI and SalI and using the Escherichia coli rrnB operon as the probe, differentiated 11 and 14 ribotypes, respectively, and a combination of data from both procedures yielded 19 combined ribotypes. Cluster analysis of the combined ribotypes differentiated the pathovars phaseolicola and syringae, as well as different clonal lineages within these pathovars. The potential of ribotyping to screen for correlations between lineages and factors such as geographical region and/or bean varieties is also reported. PMID:10653764

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2010-07-30

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

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

    International Nuclear Information System (INIS)

    Rajasekaran, Mohan B; Mitchell, Sue A; Gibson, Trevor M; Hussain, Rohanah; Siligardi, Giuliano; Andrews, Simon C; Watson, Kimberly A

    2010-01-01

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

  10. A Localized Pseudomonas syringae Infection Triggers Systemic Clock Responses in Arabidopsis.

    Science.gov (United States)

    Li, Zheng; Bonaldi, Katia; Uribe, Francisco; Pruneda-Paz, Jose L

    2018-02-19

    The circadian clock drives daily rhythms of many plant physiological responses, providing a competitive advantage that improves plant fitness and survival rates [1-5]. Whereas multiple environmental cues are predicted to regulate the plant clock function, most studies focused on understanding the effects of light and temperature [5-8]. Increasing evidence indicates a significant role of plant-pathogen interactions on clock regulation [9, 10], but the underlying mechanisms remain elusive. In Arabidopsis, the clock function largely relies on a transcriptional feedback loop between morning (CCA1 and LHY)- and evening (TOC1)-expressed transcription factors [6-8]. Here, we focused on these core components to investigate the Arabidopsis clock regulation using a unique biotic stress approach. We found that a single-leaf Pseudomonas syringae infection systemically lengthened the period and reduced the amplitude of circadian rhythms in distal uninfected tissues. Remarkably, the low-amplitude phenotype observed upon infection was recapitulated by a transient treatment with the defense-related phytohormone salicylic acid (SA), which also triggered a significant clock phase delay. Strikingly, despite SA-modulated circadian rhythms, we revealed that the master regulator of SA signaling, NPR1 [11, 12], antagonized clock responses triggered by both SA treatment and P. syringae. In contrast, we uncovered that the NADPH oxidase RBOHD [13] largely mediated the aforementioned clock responses after either SA treatment or the bacterial infection. Altogether, we demonstrated novel and unexpected roles for SA, NPR1, and redox signaling in clock regulation by P. syringae and revealed a previously unrecognized layer of systemic clock regulation by locally perceived environmental cues. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. AtMIN7 mediated disease resistance to Pseudomonas syringae in Arabidopsis

    Science.gov (United States)

    He, Sheng Yang [Okemos, MI; Nomura, Kinya [East Lansing, MI

    2011-07-26

    The present invention relates to compositions and methods for enhancing plant defenses against pathogens. More particularly, the invention relates to enhancing plant immunity against bacterial pathogens, wherein AtMIN7 mediated protection is enhanced and/or there is a decrease in activity of an AtMIN7 associated virulence protein such as a Pseudomonas syringae pv. tomato DC3000 HopM1. Reagents of the present invention provide a means of studying cellular trafficking while formulations of the present inventions provide increased pathogen resistance in plants.

  12. Pseudomonas syringae evades host Immunity by degrading flagellin monomers with alkaline protease AprA

    OpenAIRE

    Pel, M.J.C.; Van Dijken, A.J.H.; Bardoel, B.W.; Seidl, M.F; Van der Ent, S.; Van Strijp, J.A.G.

    2014-01-01

    Bacterial flagellin molecules are strong inducers of innate immune responses in both mammals and plants. The opportunistic pathogen Pseudomonas aeruginosa secretes an alkaline protease called AprA that degrades flagellin monomers. Here, we show that AprA is widespread among a wide variety of bacterial species. In addition, we investigated the role of AprA in virulence of the bacterial plant athogen P. syringae pv. tomato DC3000. The AprA-deficient DC3000 ΔaprA knockout mutant was significantl...

  13. Impaired Chloroplast Biogenesis in Immutans, an Arabidopsis Variegation Mutant, Modifies Developmental Programming, Cell Wall Composition and Resistance to Pseudomonas syringae.

    Directory of Open Access Journals (Sweden)

    Gennady V Pogorelko

    Full Text Available The immutans (im variegation mutation of Arabidopsis has green- and white- sectored leaves due to action of a nuclear recessive gene. IM codes for PTOX, a plastoquinol oxidase in plastid membranes. Previous studies have revealed that the green and white sectors develop into sources (green tissues and sinks (white tissues early in leaf development. In this report we focus on white sectors, and show that their transformation into effective sinks involves a sharp reduction in plastid number and size. Despite these reductions, cells in the white sectors have near-normal amounts of plastid RNA and protein, and surprisingly, a marked amplification of chloroplast DNA. The maintenance of protein synthesis capacity in the white sectors might poise plastids for their development into other plastid types. The green and white im sectors have different cell wall compositions: whereas cell walls in the green sectors resemble those in wild type, cell walls in the white sectors have reduced lignin and cellulose microfibrils, as well as alterations in galactomannans and the decoration of xyloglucan. These changes promote susceptibility to the pathogen Pseudomonas syringae. Enhanced susceptibility can also be explained by repressed expression of some, but not all, defense genes. We suggest that differences in morphology, physiology and biochemistry between the green and white sectors is caused by a reprogramming of leaf development that is coordinated, in part, by mechanisms of retrograde (plastid-to-nucleus signaling, perhaps mediated by ROS. We conclude that variegation mutants offer a novel system to study leaf developmental programming, cell wall metabolism and host-pathogen interactions.

  14. Origin of the Outbreak in France of Pseudomonas syringae pv. actinidiae Biovar 3, the Causal Agent of Bacterial Canker of Kiwifruit, Revealed by a Multilocus Variable-Number Tandem-Repeat Analysis.

    Science.gov (United States)

    Cunty, A; Cesbron, S; Poliakoff, F; Jacques, M-A; Manceau, C

    2015-10-01

    The first outbreaks of bacterial canker of kiwifruit caused by Pseudomonas syringae pv. actinidiae biovar 3 were detected in France in 2010. P. syringae pv. actinidiae causes leaf spots, dieback, and canker that sometimes lead to the death of the vine. P. syringae pv. actinidifoliorum, which is pathogenic on kiwi as well, causes only leaf spots. In order to conduct an epidemiological study to track the spread of the epidemics of these two pathogens in France, we developed a multilocus variable-number tandem-repeat (VNTR) analysis (MLVA). MLVA was conducted on 340 strains of P. syringae pv. actinidiae biovar 3 isolated in Chile, China, France, Italy, and New Zealand and on 39 strains of P. syringae pv. actinidifoliorum isolated in Australia, France, and New Zealand. Eleven polymorphic VNTR loci were identified in the genomes of P. syringae pv. actinidiae biovar 3 ICMP 18744 and of P. syringae pv. actinidifoliorum ICMP 18807. MLVA enabled the structuring of P. syringae pv. actinidiae biovar 3 and P. syringae pv. actinidifoliorum strains in 55 and 16 haplotypes, respectively. MLVA and discriminant analysis of principal components revealed that strains isolated in Chile, China, and New Zealand are genetically distinct from P. syringae pv. actinidiae strains isolated in France and in Italy, which appear to be closely related at the genetic level. In contrast, no structuring was observed for P. syringae pv. actinidifoliorum. We developed an MLVA scheme to explore the diversity within P. syringae pv. actinidiae biovar 3 and to trace the dispersal routes of epidemic P. syringae pv. actinidiae biovar 3 in Europe. We suggest using this MLVA scheme to trace the dispersal routes of P. syringae pv. actinidiae at a global level. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  15. Analyses of wrky18 wrky40 plants reveal critical roles of SA/EDS1 signaling and indole-glucosinolate biosynthesis for Golovinomyces orontii resistance and a loss-of resistance towards Pseudomonas syringae pv. tomato AvrRPS4.

    Science.gov (United States)

    Schön, Moritz; Töller, Armin; Diezel, Celia; Roth, Charlotte; Westphal, Lore; Wiermer, Marcel; Somssich, Imre E

    2013-07-01

    Simultaneous mutation of two WRKY-type transcription factors, WRKY18 and WRKY40, renders otherwise susceptible wild-type Arabidopsis plants resistant towards the biotrophic powdery mildew fungus Golovinomyces orontii. Resistance in wrky18 wrky40 double mutant plants is accompanied by massive transcriptional reprogramming, imbalance in salicylic acid (SA) and jasmonic acid (JA) signaling, altered ENHANCED DISEASE SUSCEPTIBILITY1 (EDS1) expression, and accumulation of the phytoalexin camalexin. Genetic analyses identified SA biosynthesis and EDS1 signaling as well as biosynthesis of the indole-glucosinolate 4MI3G as essential components required for loss-of-WRKY18 WRKY40-mediated resistance towards G. orontii. The analysis of wrky18 wrky40 pad3 mutant plants impaired in camalexin biosynthesis revealed an uncoupling of pre- from postinvasive resistance against G. orontii. Comprehensive infection studies demonstrated the specificity of wrky18 wrky40-mediated G. orontii resistance. Interestingly, WRKY18 and WRKY40 act as positive regulators in effector-triggered immunity, as the wrky18 wrky40 double mutant was found to be strongly susceptible towards the bacterial pathogen Pseudomonas syringae DC3000 expressing the effector AvrRPS4 but not against other tested Pseudomonas strains. We hypothesize that G. orontii depends on the function of WRKY18 and WRKY40 to successfully infect Arabidopsis wild-type plants while, in the interaction with P. syringae AvrRPS4, they are required to mediate effector-triggered immunity.

  16. The role of crop waste and soil in Pseudomonas syringae pathovar porri infection of leek (Allium porrum)

    NARCIS (Netherlands)

    Overbeek, van L.S.; Nijhuis, E.H.; Koenraadt, H.; Visser, J.H.M.

    2010-01-01

    Pseudomonas syringae pv. porri, the causal agent of bacterial blight of leek, is a current threat for leek (Allium porrum) production in the Netherlands. The roles of post-harvest crop waste and plant invasion from soil in leek plant infection was investigated with the purpose to gain better

  17. Virulence of Pseudomonas syringae pv. tomato DC3000 is modulated through the Catabolite Repression Control protein Crc

    Science.gov (United States)

    Pseudomonas syringae (P.s.) infects diverse plant species and several P.s. pathovars have been used in the study of molecular events that occur during plant-microbe interactions. Although the relationship between bacterial metabolism, nutrient acquisition and virulence has attracted increasing atten...

  18. Genome, Proteome and Structure of a T7-Like Bacteriophage of the Kiwifruit Canker Phytopathogen Pseudomonas syringae pv. actinidiae.

    Science.gov (United States)

    Frampton, Rebekah A; Acedo, Elena Lopez; Young, Vivienne L; Chen, Danni; Tong, Brian; Taylor, Corinda; Easingwood, Richard A; Pitman, Andrew R; Kleffmann, Torsten; Bostina, Mihnea; Fineran, Peter C

    2015-06-24

    Pseudomonas syringae pv. actinidiae is an economically significant pathogen responsible for severe bacterial canker of kiwifruit (Actinidia sp.). Bacteriophages infecting this phytopathogen have potential as biocontrol agents as part of an integrated approach to the management of bacterial canker, and for use as molecular tools to study this bacterium. A variety of bacteriophages were previously isolated that infect P. syringae pv. actinidiae, and their basic properties were characterized to provide a framework for formulation of these phages as biocontrol agents. Here, we have examined in more detail φPsa17, a phage with the capacity to infect a broad range of P. syringae pv. actinidiae strains and the only member of the Podoviridae in this collection. Particle morphology was visualized using cryo-electron microscopy, the genome was sequenced, and its structural proteins were analysed using shotgun proteomics. These studies demonstrated that φPsa17 has a 40,525 bp genome, is a member of the T7likevirus genus and is closely related to the pseudomonad phages φPSA2 and gh-1. Eleven structural proteins (one scaffolding) were detected by proteomics and φPsa17 has a capsid of approximately 60 nm in diameter. No genes indicative of a lysogenic lifecycle were identified, suggesting the phage is obligately lytic. These features indicate that φPsa17 may be suitable for formulation as a biocontrol agent of P. syringae pv. actinidiae.

  19. Indole-3-acetaldehyde dehydrogenase-dependent auxin synthesis contributes to virulence of Pseudomonas syringae strain DC3000.

    Directory of Open Access Journals (Sweden)

    Sheri A McClerklin

    2018-01-01

    Full Text Available The bacterial pathogen Pseudomonas syringae modulates plant hormone signaling to promote infection and disease development. P. syringae uses several strategies to manipulate auxin physiology in Arabidopsis thaliana to promote pathogenesis, including its synthesis of indole-3-acetic acid (IAA, the predominant form of auxin in plants, and production of virulence factors that alter auxin responses in the host; however, the role of pathogen-derived auxin in P. syringae pathogenesis is not well understood. Here we demonstrate that P. syringae strain DC3000 produces IAA via a previously uncharacterized pathway and identify a novel indole-3-acetaldehyde dehydrogenase, AldA, that functions in IAA biosynthesis by catalyzing the NAD-dependent formation of IAA from indole-3-acetaldehyde (IAAld. Biochemical analysis and solving of the 1.9 Å resolution x-ray crystal structure reveal key features of AldA for IAA synthesis, including the molecular basis of substrate specificity. Disruption of aldA and a close homolog, aldB, lead to reduced IAA production in culture and reduced virulence on A. thaliana. We use these mutants to explore the mechanism by which pathogen-derived auxin contributes to virulence and show that IAA produced by DC3000 suppresses salicylic acid-mediated defenses in A. thaliana. Thus, auxin is a DC3000 virulence factor that promotes pathogenicity by suppressing host defenses.

  20. Genome, Proteome and Structure of a T7-Like Bacteriophage of the Kiwifruit Canker Phytopathogen Pseudomonas Syringae pv. Actinidiae

    Directory of Open Access Journals (Sweden)

    Rebekah A. Frampton

    2015-06-01

    Full Text Available Pseudomonas syringae pv. actinidiae is an economically significant pathogen responsible for severe bacterial canker of kiwifruit (Actinidia sp.. Bacteriophages infecting this phytopathogen have potential as biocontrol agents as part of an integrated approach to the management of bacterial canker, and for use as molecular tools to study this bacterium. A variety of bacteriophages were previously isolated that infect P. syringae pv. actinidiae, and their basic properties were characterized to provide a framework for formulation of these phages as biocontrol agents. Here, we have examined in more detail φPsa17, a phage with the capacity to infect a broad range of P. syringae pv. actinidiae strains and the only member of the Podoviridae in this collection. Particle morphology was visualized using cryo-electron microscopy, the genome was sequenced, and its structural proteins were analysed using shotgun proteomics. These studies demonstrated that φPsa17 has a 40,525 bp genome, is a member of the T7likevirus genus and is closely related to the pseudomonad phages φPSA2 and gh-1. Eleven structural proteins (one scaffolding were detected by proteomics and φPsa17 has a capsid of approximately 60 nm in diameter. No genes indicative of a lysogenic lifecycle were identified, suggesting the phage is obligately lytic. These features indicate that φPsa17 may be suitable for formulation as a biocontrol agent of P. syringae pv. actinidiae.

  1. Novel Pseudomonas syringae strains associated with leaf spot diseases on watermelon (Citrullus lanatus) and squash (Cucurbita pepo) in California

    Science.gov (United States)

    In 2006 and 2011, bacteria, fluorescent on KMB, were isolated from leaf spots of greenhouse-grown watermelon (Citrullus lanatus) and field-grown squash (Cucurbita pepo) in coastal California. Biochemical characterization of the isolates indicated that they belonged to Pseudomonas syringae. Multilocu...

  2. The plant pathogen Pseudomonas syringae pv. tomato is genetically monomorphic and under strong selection to evade tomato immunity.

    Directory of Open Access Journals (Sweden)

    Rongman Cai

    2011-08-01

    Full Text Available Recently, genome sequencing of many isolates of genetically monomorphic bacterial human pathogens has given new insights into pathogen microevolution and phylogeography. Here, we report a genome-based micro-evolutionary study of a bacterial plant pathogen, Pseudomonas syringae pv. tomato. Only 267 mutations were identified between five sequenced isolates in 3,543,009 nt of analyzed genome sequence, which suggests a recent evolutionary origin of this pathogen. Further analysis with genome-derived markers of 89 world-wide isolates showed that several genotypes exist in North America and in Europe indicating frequent pathogen movement between these world regions. Genome-derived markers and molecular analyses of key pathogen loci important for virulence and motility both suggest ongoing adaptation to the tomato host. A mutational hotspot was found in the type III-secreted effector gene hopM1. These mutations abolish the cell death triggering activity of the full-length protein indicating strong selection for loss of function of this effector, which was previously considered a virulence factor. Two non-synonymous mutations in the flagellin-encoding gene fliC allowed identifying a new microbe associated molecular pattern (MAMP in a region distinct from the known MAMP flg22. Interestingly, the ancestral allele of this MAMP induces a stronger tomato immune response than the derived alleles. The ancestral allele has largely disappeared from today's Pto populations suggesting that flagellin-triggered immunity limits pathogen fitness even in highly virulent pathogens. An additional non-synonymous mutation was identified in flg22 in South American isolates. Therefore, MAMPs are more variable than expected differing even between otherwise almost identical isolates of the same pathogen strain.

  3. Arabidopsis AtERF15 positively regulates immunity against Pseudomonas syringae pv. tomato DC3000 and Botrytis cinerea

    Directory of Open Access Journals (Sweden)

    Huijuan eZhang

    2015-09-01

    Full Text Available Upon pathogen infection, activation of immune response requires effective transcriptional reprogramming that regulates inducible expression of a large set of defense genes. A number of ethylene-responsive factor transcription factors have been shown to play critical roles in regulating immune responses in plants. In the present study, we explored the functions of Arabidopsis AtERF15 in immune responses against Pseudomonas syringae pv. tomato (Pst DC3000, a (hemibiotrophic bacterial pathogen, and Botrytis cinerea, a necrotrophic fungal pathogen. Expression of AtERF15 was induced by infection of Pst DC3000 and B. cinerea and by treatments with salicylic acid (SA and methyl jasmonate. Biochemical assays demonstrated that AtERF15 is a nucleus-localized transcription activator. The AtERF15-overexpressing (AtERF15-OE plants displayed enhanced resistance while the AtERF15-RNAi plants exhibited decreased resistance against Pst DC3000 and B. cinerea. Meanwhile, Pst DC3000- or B. cinerea-induced expression of defense genes was upregulated in AtERF15-OE plants but downregulated in AtERF15-RNAi plants, as compared to the expression in wild type plants. In response to infection with B. cinerea, the AtERF15-OE plants accumulated less reactive oxygen species (ROS while the AtERF15-RNAi plants accumulated more ROS. The flg22- and chitin-induced oxidative burst was abolished and expression levels of the pattern-triggered immunity-responsive genes AtFRK1 and AtWRKY53 were suppressed in AtER15-RNAi plants upon treatment with flg22 or chitin. Furthermore, SA-induced defense response was also partially impaired in the AtERF15-RNAi plants. These data demonstrate that AtERF15 is a positive regulator of multiple layers of the immune responses in Arabidopsis.

  4. Genomic analysis of the Kiwifruit pathogen Pseudomonas syringae pv. actinidiae provides insight into the origins of an emergent plant disease.

    Directory of Open Access Journals (Sweden)

    Honour C McCann

    Full Text Available The origins of crop diseases are linked to domestication of plants. Most crops were domesticated centuries--even millennia--ago, thus limiting opportunity to understand the concomitant emergence of disease. Kiwifruit (Actinidia spp. is an exception: domestication began in the 1930s with outbreaks of canker disease caused by P. syringae pv. actinidiae (Psa first recorded in the 1980s. Based on SNP analyses of two circularized and 34 draft genomes, we show that Psa is comprised of distinct clades exhibiting negligible within-clade diversity, consistent with disease arising by independent samplings from a source population. Three clades correspond to their geographical source of isolation; a fourth, encompassing the Psa-V lineage responsible for the 2008 outbreak, is now globally distributed. Psa has an overall clonal population structure, however, genomes carry a marked signature of within-pathovar recombination. SNP analysis of Psa-V reveals hundreds of polymorphisms; however, most reside within PPHGI-1-like conjugative elements whose evolution is unlinked to the core genome. Removal of SNPs due to recombination yields an uninformative (star-like phylogeny consistent with diversification of Psa-V from a single clone within the last ten years. Growth assays provide evidence of cultivar specificity, with rapid systemic movement of Psa-V in Actinidia chinensis. Genomic comparisons show a dynamic genome with evidence of positive selection on type III effectors and other candidate virulence genes. Each clade has highly varied complements of accessory genes encoding effectors and toxins with evidence of gain and loss via multiple genetic routes. Genes with orthologs in vascular pathogens were found exclusively within Psa-V. Our analyses capture a pathogen in the early stages of emergence from a predicted source population associated with wild Actinidia species. In addition to candidate genes as targets for resistance breeding programs, our findings

  5. Plant innate immunity induced by flagellin suppresses the hypersensitive response in non-host plants elicited by Pseudomonas syringae pv. averrhoi.

    Directory of Open Access Journals (Sweden)

    Chia-Fong Wei

    Full Text Available A new pathogen, Pseudomonas syringae pv. averrhoi (Pav, which causes bacterial spot disease on carambola was identified in Taiwan in 1997. Many strains of this pathovar have been isolated from different locations and several varieties of hosts. Some of these strains, such as HL1, are nonmotile and elicit a strong hypersensitive response (HR in nonhost tobacco leaves, while other strains, such as PA5, are motile and elicit a weak HR. Based on the image from a transmission electron microscope, the results showed that HL1 is flagellum-deficient and PA5 has normal flagella. Here we cloned and analyzed the fliC gene and glycosylation island from Pav HL1 and PA5. The amino acid sequences of FliC from HL1 and PA5 are identical to P. s. pvs. tabaci (Pta, glycinea and phaseolicola and share very high similarity with other pathovars of P. syringae. In contrast to the flagellin mutant PtaΔfliC, PA5ΔfliC grows as well as wild type in the host plant, but it elicits stronger HR than wild type does in non-host plants. Furthermore, the purified Pav flagellin, but not the divergent flagellin from Agrobacterium tumefaciens, is able to impair the HR induced by PA5ΔfliC. PA5Δfgt1 possessing nonglycosylated flagella behaved as its wild type in both bacterial growth in host and HR elicitation. Flagellin was infiltrated into tobacco leaves either simultaneously with flagellum-deficient HL1 or prior to the inoculation of wild type HL1, and both treatments impaired the HR induced by HL1. Moreover, the HR elicited by PA5 and PA5ΔfliC was enhanced by the addition of cycloheximide, suggesting that the flagellin is one of the PAMPs (pathogen-associated molecular patterns contributed to induce the PAMP-triggered immunity (PTI. Taken together, the results shown in this study reveal that flagellin in Pav is capable of suppressing HR via PTI induction during an incompatible interaction.

  6. Abscisic acid-cytokinin antagonism modulates resistance against pseudomonas syringae in Tobacco

    DEFF Research Database (Denmark)

    Grosskinsky, Dominik Kilian; van der Graaff, Eric; Roitsch, Thomas Georg

    2014-01-01

    Phytohormones are known as essential regulators of plant defenses, with ethylene, jasmonic acid, and salicylic acid as the central immunity backbone, while other phytohormones have been demonstrated to interact with this. Only recently, a function of the classic phytohormone cytokinin in plant...... immunity has been described in Arabidopsis, rice, and tobacco. Although interactions of cytokinins with salicylic acid and auxin have been indicated, the complete network of cytokinin interactions with other immunity-relevant phytohormones is not yet understood. Therefore, we studied the interaction...... of kinetin and abscisic acid as a negative regulator of plant immunity to modulate resistance in tobacco against Pseudomonas syringae. By analyzing infection symptoms, pathogen proliferation, and accumulation of the phytoalexin scopoletin as a key mediator of kinetin-induced resistance in tobacco...

  7. Contribution of alginate and levan production to biofilm formation by Pseudomonas syringae

    DEFF Research Database (Denmark)

    Laue, H.; Schenk, A.; Li, H.

    2006-01-01

    Exopolysaccharides (EPSs) play important roles in the attachment of bacterial cells to a surface and/or in building and maintaining the three-dimensional, complex structure of bacterial biofilms. To elucidate the spatial distribution and function of the EPSs levan and alginate during biofilm...... formation, biofilms of Pseudomonas syringae strains with different EPS patterns were compared. The mucoid strain PG4180.muc, which produces levan and alginate, and its levan- and/or alginate-deficient derivatives all formed biofilms in the wells of microtitre plates and in flow chambers. Confocal laser...... scanning microscopy with fluorescently labelled lectins was applied to investigate the spatial distribution of levan and an additional as yet unknown EPS in flow-chamber biofilms. Concanavalin A (ConA) bound specifically to levan and accumulated in cell-depleted voids in the centres of microcolonies...

  8. Phenolic composition, antioxidant and antinociceptive activities of Syringa vulgaris L. bark and leaf extracts.

    Science.gov (United States)

    Varga, Erzsébet; Barabás, Csenge; Tóth, Anita; Boldizsár, Imre; Noszál, Béla; Tóth, Gergő

    2018-01-16

    Metabolite profile, antioxidant and antinociceptive activities of Syringa vulgaris bark and leaf methanolic extracts were investigated. By means of HPLC-DAD-ESI-TOF and HPLC-DAD-ESI-MS/MS, a total of 33 phenolics were identified, including 15 secoiridoids, 6 phenylpropanoids, 3 flavonoids, 3 lignans and 6 low molecular weight phenols. Validated quantitative analysis show that syringin (2.52%) and rutin (1.13%) are the main phenolic compounds in bark and leaf, respectively. Notable radical scavenging and antinociceptive activities of the bark and leaf extracts were confirmed by in vitro DPPH ● and ABTS ●+ assays and by in vivo hot-plate method in mice, respectively. Our results could lay the scientific basic of future clinical perspectives of lilac bark and leaf.

  9. Assessment of strains of Pseudomonas syringae pv. tomato from Tanzania for resistance to copper and streptomycin

    DEFF Research Database (Denmark)

    Shenge, K.C.; Wydra, K.; Mabagala, M.B.

    2008-01-01

    Fifty-six strains of Pseudomonas syringae pv. tomato (P.s. pv. tomato) were collected from tomato-producing areas in Tanzania and assessed for resistance to copper and antibiotics. The collection was done from three tomato-producing regions (Morogoro, Arusha and Iringa), representing three...... different ecological conditions in the country. After isolation and identification, the P. s. pv. tomato strains were grown on King's medium B (KB) amended with 20% copper sulphate (w/v). The strains were also assessed for resistance to antibiotics. Results indicated that there was widespread resistance...... of the P. s. pv. tomato strains to copper sulphate. The highest level of resistance was recorded from the Arusha region (Northern Tanzania), 83.3% of the P. s. pv. tomato strains from that region showed resistance to copper sulphate. This was followed by Iringa region (Southern Tanzania), from where...

  10. Transcriptome Analysis of Syringa oblata Lindl. Inflorescence Identifies Genes Associated with Pigment Biosynthesis and Scent Metabolism.

    Directory of Open Access Journals (Sweden)

    Jian Zheng

    Full Text Available Syringa oblata Lindl. is a woody ornamental plant with high economic value and characteristics that include early flowering, multiple flower colors, and strong fragrance. Despite a long history of cultivation, the genetics and molecular biology of S. oblata are poorly understood. Transcriptome and expression profiling data are needed to identify genes and to better understand the biological mechanisms of floral pigments and scents in this species. Nine cDNA libraries were obtained from three replicates of three developmental stages: inflorescence with enlarged flower buds not protruded, inflorescence with corolla lobes not displayed, and inflorescence with flowers fully opened and emitting strong fragrance. Using the Illumina RNA-Seq technique, 319,425,972 clean reads were obtained and were assembled into 104,691 final unigenes (average length of 853 bp, 41.75% of which were annotated in the NCBI non-redundant protein database. Among the annotated unigenes, 36,967 were assigned to gene ontology categories and 19,956 were assigned to eukaryoticorthologous groups. Using the Kyoto Encyclopedia of Genes and Genomes pathway database, 12,388 unigenes were sorted into 286 pathways. Based on these transcriptomic data, we obtained a large number of candidate genes that were differentially expressed at different flower stages and that were related to floral pigment biosynthesis and fragrance metabolism. This comprehensive transcriptomic analysis provides fundamental information on the genes and pathways involved in flower secondary metabolism and development in S. oblata, providing a useful database for further research on S. oblata and other plants of genus Syringa.

  11. Protection of Tomato Seedlings against Infection by Pseudomonas syringae pv. Tomato by Using the Plant Growth-Promoting Bacterium Azospirillum brasilense†

    Science.gov (United States)

    Bashan, Yoav; de-Bashan, Luz E.

    2002-01-01

    Pseudomonas syringae pv. tomato, the causal agent of bacterial speck of tomato, and the plant growth-promoting bacterium Azospirillum brasilense were inoculated onto tomato plants, either alone, as a mixed culture, or consecutively. The population dynamics in the rhizosphere and foliage, the development of bacterial speck disease, and their effects on plant growth were monitored. When inoculated onto separate plants, the A. brasilense population in the rhizosphere of tomato plants was 2 orders of magnitude greater than the population of P. syringae pv. tomato (107 versus 105 CFU/g [dry weight] of root). Under mist chamber conditions, the leaf population of P. syringae pv. tomato was 1 order of magnitude greater than that of A. brasilense (107 versus 106 CFU/g [dry weight] of leaf). Inoculation of seeds with a mixed culture of the two bacterial strains resulted in a reduction of the pathogen population in the rhizosphere, an increase in the A. brasilense population, the prevention of bacterial speck disease development, and improved plant growth. Inoculation of leaves with the mixed bacterial culture under mist conditions significantly reduced the P. syringae pv. tomato population and significantly decreased disease severity. Challenge with P. syringae pv. tomato after A. brasilense was established in the leaves further reduced both the population of P. syringae pv. tomato and disease severity and significantly enhanced plant development. Both bacteria maintained a large population in the rhizosphere for 45 days when each was inoculated separately onto tomato seeds (105 to 106 CFU/g [dry weight] of root). However, P. syringae pv. tomato did not survive in the rhizosphere in the presence of A. brasilense. Foliar inoculation of A. brasilense after P. syringae pv. tomato was established on the leaves did not alleviate bacterial speck disease, and A. brasilense did not survive well in the phyllosphere under these conditions, even in a mist chamber. Several applications

  12. The stealth episome: suppression of gene expression on the excised genomic island PPHGI-1 from Pseudomonas syringae pv. phaseolicola.

    Directory of Open Access Journals (Sweden)

    Scott A C Godfrey

    2011-03-01

    Full Text Available Pseudomonas syringae pv. phaseolicola is the causative agent of halo blight in the common bean, Phaseolus vulgaris. P. syringae pv. phaseolicola race 4 strain 1302A contains the avirulence gene avrPphB (syn. hopAR1, which resides on PPHGI-1, a 106 kb genomic island. Loss of PPHGI-1 from P. syringae pv. phaseolicola 1302A following exposure to the hypersensitive resistance response (HR leads to the evolution of strains with altered virulence. Here we have used fluorescent protein reporter systems to gain insight into the mobility of PPHGI-1. Confocal imaging of dual-labelled P. syringae pv. phaseolicola 1302A strain, F532 (dsRFP in chromosome and eGFP in PPHGI-1, revealed loss of PPHGI-1::eGFP encoded fluorescence during plant infection and when grown in vitro on extracted leaf apoplastic fluids. Fluorescence-activated cell sorting (FACS of fluorescent and non-fluorescent PPHGI-1::eGFP F532 populations showed that cells lost fluorescence not only when the GI was deleted, but also when it had excised and was present as a circular episome. In addition to reduced expression of eGFP, quantitative PCR on sub-populations separated by FACS showed that transcription of other genes on PPHGI-1 (avrPphB and xerC was also greatly reduced in F532 cells harbouring the excised PPHGI-1::eGFP episome. Our results show how virulence determinants located on mobile pathogenicity islands may be hidden from detection by host surveillance systems through the suppression of gene expression in the episomal state.

  13. The Arabidopsis thaliana non-specific phospholipase C2 is involved in the response to Pseudomonas syringae attack

    Czech Academy of Sciences Publication Activity Database

    Krčková, Zuzana; Kocourková, Daniela; Daněk, Michal; Brouzdová, Jitka; Pejchar, Přemysl; Janda, Martin; Pokotylo, I.; Ott, P.G.; Valentová, O.; Martinec, Jan

    2018-01-01

    Roč. 121, č. 2 (2018), s. 297-310 ISSN 0305-7364 R&D Projects: GA ČR(CZ) GAP501/12/1942 Institutional support: RVO:61389030 Keywords : Arabidopsis thaliana * effector-triggered immunity * flagellin * MAMP-triggered immunity * non-specific phospholipase C * phosphatidylcholine-specific phospholipase C * Pseudomonas syringae * reactive oxygen species Subject RIV: ED - Physiology OBOR OECD: Plant sciences, botany Impact factor: 4.041, year: 2016

  14. Comparison of the complete genome sequences of Pseudomonassyringae pv. syringae B728a and pv. tomato DC3000.

    Energy Technology Data Exchange (ETDEWEB)

    Feil, Helene; Feil, William S.; Chain, Patrick; Larimer, Frank; DiBartolo, Genevieve; Copeland, Alex; Lykidis, Athanasios; Trong,Stephen; Nolan, Matt; Goltsman, Eugene; Thiel, James; Malfatti,Stephanie; Loper, Joyce E.; Lapidus, Alla; Detter, John C.; Land, Miriam; Richardson, Paul M.; Kyrpides, Nikos C.; Ivanova, Natalia; Lindow, StevenE.

    2005-04-01

    The complete genomic sequence of Pseudomonas syringaepathovar syringae B728a (Pss B728a), has been determined and is comparedwith that of Pseudomonas syringae pv. tomato DC3000 (Pst DC3000). Thesetwo pathovars of this economically important species of plant pathogenicbacteria differ in host range and apparent patterns of interaction withplants, with Pss having a more pronounced epiphytic stage of growth andhigher abiotic stress tolerance and Pst DC3000 having a more pronouncedapoplastic growth habitat. The Pss B728a genome (6.1 megabases) containsa circular chromosome and no plasmid, whereas the Pst DC3000 genome is6.5 mbp in size, composed of a circular chromosome and two plasmids.While a high degree of similarity exists between the two sequencedPseudomonads, 976 protein-encoding genes are unique to Pss B728a whencompared to Pst DC3000, including large genomic islands likely tocontribute to virulence and host specificity. Over 375 repetitiveextragenic palindromic sequences (REPs) unique to Pss B728a when comparedto Pst DC3000 are widely distributed throughout the chromosome except in14 genomic islands, which generally had lower GC content than the genomeas a whole. Content of the genomic islands vary, with one containing aprophage and another the plasmid pKLC102 of P. aeruginosa PAO1. Among the976 genes of Pss B728a with no counterpart in Pst DC3000 are thoseencoding for syringopeptin (SP), syringomycin (SR), indole acetic acidbiosynthesis, arginine degradation, and production of ice nuclei. Thegenomic comparison suggests that several unique genes for Pss B728a suchas ectoine synthase, DNA repair, and antibiotic production may contributeto epiphytic fitness and stress tolerance of this organism. Pseudomonassyringae, a member of the gamma subgroup of the Proteobacteria, is awidespread bacterial pathogen of many plant species. The species P.syringae is subdivided into approximately 50 pathovars based onpathogenicity and host range. P. syringae is capable of

  15. Biocontrol of postharvest decay using a new strain of Pseudomonas syringae CPA-5 in different cultivars of pome fruits

    Directory of Open Access Journals (Sweden)

    C. NUNES

    2008-12-01

    Full Text Available Epiphytic micro-organisms isolated from fruits and leaves surfaces of apples from different orchards were screened for antagonistic activity against Penicillium expansum. From all micro-organisms tested the new strain CPA-5 of Pseudomonas syringae, isolated from organic orchard, was selected. This strain was very effective against Botrytis cinerea, P. expansum and Rhizopus stolonifer at various antagonist and pathogen concentrations on ‘Golden Delicious’ apple, and ‘Blanquilla’, ‘Rocha’ and ‘Conference’ pear. Under cold storage conditions and in semi-commercial trials P. syringae (CPA-5 significantly reduced development of P. expansum and B. cinerea on ‘Golden Delicious’ apple, and ‘Blanquilla’ and ‘Rocha’ pears. Control of P. expansum equal to the fungicide imazalil was obtained with CPA-5 at 108cfu ml–1 on ‘Gold Delicious’ apple and ‘Rocha’ pear. The populations of P. syringae CPA-5 increased more than 100-fold during the first 50 days, and then remained stable on apple, and slightly decreased on pears. This indicates the high capacity of this antagonist to colonize wound surfaces of pome fruits under cold storage conditions.;

  16. Mutations in LACS2, a long-chain acyl-coenzyme A synthetase, enhance susceptibility to avirulent Pseudomonas syringae but confer resistance to Botrytis cinerea in Arabidopsis.

    Science.gov (United States)

    Tang, Dingzhong; Simonich, Michael T; Innes, Roger W

    2007-06-01

    We identified an Arabidopsis (Arabidopsis thaliana) mutant, sma4 (symptoms to multiple avr genotypes4), that displays severe disease symptoms when inoculated with avirulent strains of Pseudomonas syringae pv tomato, although bacterial growth is only moderately enhanced compared to wild-type plants. The sma4 mutant showed a normal susceptible phenotype to the biotrophic fungal pathogen Erysiphe cichoracearum. Significantly, the sma4 mutant was highly resistant to a necrotrophic fungal pathogen, Botrytis cinerea. Germination of B. cinerea spores on sma4 mutant leaves was inhibited, and penetration by those that did germinate was rare. The sma4 mutant also showed several pleiotropic phenotypes, including increased sensitivity to lower humidity and salt stress. Isolation of SMA4 by positional cloning revealed that it encodes LACS2, a member of the long-chain acyl-CoA synthetases. LACS2 has previously been shown to be involved in cutin biosynthesis. We therefore tested three additional cutin-defective mutants for resistance to B. cinerea: att1 (for aberrant induction of type three genes), bodyguard, and lacerata. All three displayed an enhanced resistance to B. cinerea. Our results indicate that plant cutin or cuticle structure may play a crucial role in tolerance to biotic and abiotic stress and in the pathogenesis of B. cinerea.

  17. A genetic screen reveals Arabidopsis stomatal and/or apoplastic defenses against Pseudomonas syringae pv. tomato DC3000.

    Directory of Open Access Journals (Sweden)

    Weiqing Zeng

    2011-10-01

    Full Text Available Bacterial infection of plants often begins with colonization of the plant surface, followed by entry into the plant through wounds and natural openings (such as stomata, multiplication in the intercellular space (apoplast of the infected tissues, and dissemination of bacteria to other plants. Historically, most studies assess bacterial infection based on final outcomes of disease and/or pathogen growth using whole infected tissues; few studies have genetically distinguished the contribution of different host cell types in response to an infection. The phytotoxin coronatine (COR is produced by several pathovars of Pseudomonas syringae. COR-deficient mutants of P. s. tomato (Pst DC3000 are severely compromised in virulence, especially when inoculated onto the plant surface. We report here a genetic screen to identify Arabidopsis mutants that could rescue the virulence of COR-deficient mutant bacteria. Among the susceptible to coronatine-deficient Pst DC3000 (scord mutants were two that were defective in stomatal closure response, two that were defective in apoplast defense, and four that were defective in both stomatal and apoplast defense. Isolation of these three classes of mutants suggests that stomatal and apoplastic defenses are integrated in plants, but are genetically separable, and that COR is important for Pst DC3000 to overcome both stomatal guard cell- and apoplastic mesophyll cell-based defenses. Of the six mutants defective in bacterium-triggered stomatal closure, three are defective in salicylic acid (SA-induced stomatal closure, but exhibit normal stomatal closure in response to abscisic acid (ABA, and scord7 is compromised in both SA- and ABA-induced stomatal closure. We have cloned SCORD3, which is required for salicylic acid (SA biosynthesis, and SCORD5, which encodes an ATP-binding cassette (ABC protein, AtGCN20/AtABCF3, predicted to be involved in stress-associated protein translation control. Identification of SCORD5 begins to

  18. Early Arabidopsis root hair growth stimulation by pathogenic strains of Pseudomonas syringae.

    Science.gov (United States)

    Pecenková, Tamara; Janda, Martin; Ortmannová, Jitka; Hajná, Vladimíra; Stehlíková, Zuzana; Žárský, Viktor

    2017-09-01

    Selected beneficial Pseudomonas spp. strains have the ability to influence root architecture in Arabidopsis thaliana by inhibiting primary root elongation and promoting lateral root and root hair formation. A crucial role for auxin in this long-term (1week), long-distance plant-microbe interaction has been demonstrated. Arabidopsis seedlings were cultivated in vitro on vertical plates and inoculated with pathogenic strains Pseudomonas syringae pv. maculicola (Psm) and P. syringae pv. tomato DC3000 (Pst), as well as Agrobacterium tumefaciens (Atu) and Escherichia coli (Eco). Root hair lengths were measured after 24 and 48h of direct exposure to each bacterial strain. Several Arabidopsis mutants with impaired responses to pathogens, impaired ethylene perception and defects in the exocyst vesicle tethering complex that is involved in secretion were also analysed. Arabidopsis seedling roots infected with Psm or Pst responded similarly to when infected with plant growth-promoting rhizobacteria; root hair growth was stimulated and primary root growth was inhibited. Other plant- and soil-adapted bacteria induced similar root hair responses. The most compromised root hair growth stimulation response was found for the knockout mutants exo70A1 and ein2. The single immune pathways dependent on salicylic acid, jasmonic acid and PAD4 are not directly involved in root hair growth stimulation; however, in the mutual cross-talk with ethylene, they indirectly modify the extent of the stimulation of root hair growth. The Flg22 peptide does not initiate root hair stimulation as intact bacteria do, but pretreatment with Flg22 prior to Psm inoculation abolished root hair growth stimulation in an FLS2 receptor kinase-dependent manner. These early response phenomena are not associated with changes in auxin levels, as monitored with the pDR5::GUS auxin reporter. Early stimulation of root hair growth is an effect of an unidentified component of living plant pathogenic bacteria. The root

  19. The Arabidopsis thaliana cysteine-rich receptor-like kinase CRK20 modulates host responses to Pseudomonas syringae pv. tomato DC3000 infection

    KAUST Repository

    Ederli, Luisa

    2011-10-01

    In plants, the cysteine-rich repeat kinases (CRKs) are a sub-family of receptor-like protein kinases that contain the DUF26 motif in their extracellular domains. It has been shown that in Arabidopsis thaliana, CRK20 is transcriptionally induced by pathogens, salicylic acid and ozone (O3). However, its role in responses to biotic and abiotic stress remains to be elucidated. To determine the function of CRK20 in such responses, two CRK20 loss-of-function mutants, crk20-1 and crk20-2, were isolated from public collections of Arabidopsis T-DNA tagged lines and examined for responses to O3 and Pseudomonas syringae pv. tomato (Pst) DC3000. crk20-1 and crk20-2 showed similar O3 sensitivities and no differences in the expression of defense genes when compared with the wild-type. However, pathogen growth was significantly reduced, while there were no differences in the induction of salicylic acid related defense genes or salicylic acid accumulation. Furthermore, correlation analysis of CRK20 gene expression suggests that it has a role in the control of H2O and/or nutrient transport. We therefore propose that CRK20 promotes conditions that are favorable for Pst DC3000 growth in Arabidopsis, possibly through the regulation of apoplastic homeostasis, and consequently, of the environment of this biotrophic pathogen. © 2011 Elsevier GmbH.

  20. Phenology of lilac (Syringa vulgaris) and elderberry (Sambucus nigra) as the indicator of spring warming

    Science.gov (United States)

    Vincze, E.; Hunkár, M.; Dunkel, Z.

    2012-04-01

    Phenological observations in Hungary started in 1871. The observation system collapsed and revived time by time. The aim of the observations as well as the locations, the methods and observed plants have been changed many times, therefore data series for a given plant species derived from the same place are rare. If we want to study the responses of biosphere to climate variability we need long time data series from the same places, especially phenological data of native plants. Phenological observations organized by the Hungarian Meteorological Service between 1983- 1999 contain valuable data for lilac (Syringa vulgaris) and elderberry (Sambucus nigra). Those perennial native plants are good indicators of spring warming therefore it is worth to study their phenological development concerning to climate variability. Eight locations in Hungary were selected where the site of the observations remaind the same year by year. Observed phenological phases were: Sprouting of leaves (SL, BBCH:11); Begin of Flowers (BF, BBCH:61); Fall of leaves (FO, BBCH:95). Spatial and temporal trends and variability of phenophases will be presented. The effect of meteorological conditions is studied to build up phenological model controlled by the temperature. Growing degree days above the base temperature was involved together with the duration and severeness of the chilling period. The study is supported by the National Scientific Foundation (OTKA-81979).

  1. The antibacterial activity of syringopicroside, its metabolites and natural analogues from syringae folium

    KAUST Repository

    Zhou, Zhengyuan

    2016-02-18

    In the present study, the in vitro antibacterial activity of an effective fraction (ESF) from Syringae Folium (SF) on Methicillin-resistant Staphylococcus aureus (MRSA) was evaluated and then its in vivo activity was evaluated by using the MRSA-infected mouse peritonitis model. The ESF showed a significant in vitro and in vivo activity on decreasing the Minimum Inhibitory Concentrations (MICs) and increasing the survival rate of mouse from 42.8% to 100%. Six iridoid glucosides (IGs) of ESF were characterized by UPLC-TOF-MS method and also isolated by column chromatography. Most of them showed in vitro anti MRSA activity. Syringopicroside (Sy), the major compound of IGs, was found to increase the survival rate from 42.8% to 92.8% of the MRSA-infected mouse, which revealed Sy is also the main active components of ESF. In order to know why the effect of oral administration of SF is better than its injections in clinic and the metabolites of Sy, seven metabolites of Sy were isolated from rat urine and identified on the basis of NMR and MS spectra. Most of metabolites possessed stronger in vitro anti-MRSA activity than that of Sy, which furtherly proved the clinical result.

  2. Dissection of Resistance Genes to Pseudomonas syringae pv. phaseolicola in UI3 Common Bean Cultivar.

    Science.gov (United States)

    González, Ana M; Godoy, Luís; Santalla, Marta

    2017-11-23

    Few quantitative trait loci have been mapped for resistance to Pseudomonas syringae pv. phaseolicola in common bean. Two F₂ populations were developed from the host differential UI3 cultivar. The objective of this study was to further characterize the resistance to races 1, 5, 7 and 9 of Psp included in UI3. Using a QTL mapping approach, 16 and 11 main-effect QTLs for pod and primary leaf resistance were located on LG10, explaining up to 90% and 26% of the phenotypic variation, respectively. The homologous genomic region corresponding to primary leaf resistance QTLs detected tested positive for the presence of resistance-associated gene cluster encoding nucleotide-binding and leucine-rich repeat (NL), Natural Resistance Associated Macrophage (NRAMP) and Pentatricopeptide Repeat family (PPR) proteins. It is worth noting that the main effect QTLs for resistance in pod were located inside a 3.5 Mb genomic region that included the Phvul.010G021200 gene, which encodes a protein that has the highest sequence similarity to the RIN4 gene of Arabidopsis, and can be considered an important candidate gene for the organ-specific QTLs identified here. These results support that resistance to Psp from UI3 might result from the immune response activated by combinations of R proteins, and suggest the guard model as an important mechanism in pod resistance to halo blight. The candidate genes identified here warrant functional studies that will help in characterizing the actual defense gene(s) in UI3 genotype.

  3. Optimal level of Purple Acid Phosphatase5 is required for maintaining complete resistance to Pseudomonas syringae

    Directory of Open Access Journals (Sweden)

    Sridhar eRavichandran

    2015-08-01

    Full Text Available Plants possess an exceedingly complex innate immune system to defend against most pathogens. However, a relative proportion of the pathogens overcome host’s innate immunity and impair plant growth and productivity. We previously showed that mutation in purple acid phosphatase (PAP5 lead to enhanced susceptibility of Arabidopsis to the bacterial pathogen Pseudomonas syringae pv tomato DC3000 (Pst DC3000. Here, we report that an optimal level of PAP5 is crucial for mounting complete basal resistance. Overexpression of PAP5 impaired ICS1, PR1 expression and salicylic acid (SA accumulation similar to pap5 knockout mutant plants. Moreover, plant overexpressing PAP5 was impaired in H2O2 accumulation in response to Pst DC3000. PAP5 is localized in to peroxisomes, a known site of generation of reactive oxygen species for activation of defense responses. Taken together, our results demonstrate that optimal levels of PAP5 is required for mounting resistance against Pst DC3000 as both knockout and overexpression of PAP5 lead to compromised basal resistance.

  4. Identification, Cloning, and Characterization of l-Phenylserine Dehydrogenase from Pseudomonas syringae NK-15

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    Sakuko Ueshima

    2010-01-01

    Full Text Available The gene encoding d-phenylserine dehydrogenase from Pseudomonas syringae NK-15 was identified, and a 9,246-bp nucleotide sequence containing the gene was sequenced. Six ORFs were confirmed in the sequenced region, four of which were predicted to form an operon. A homology search of each ORF predicted that orf3 encoded l-phenylserine dehydrogenase. Hence, orf3 was cloned and overexpressed in Escherichia coli cells and recombinant ORF3 was purified to homogeneity and characterized. The purified ORF3 enzyme showed l-phenylserine dehydrogenase activity. The enzymological properties and primary structure of l-phenylserine dehydrogenase (ORF3 were quite different from those of d-phenylserine dehydrogenase previously reported. l-Phenylserine dehydrogenase catalyzed the NAD+-dependent oxidation of the β-hydroxyl group of l-β-phenylserine. l-Phenylserine and l-threo-(2-thienylserine were good substrates for l-phenylserine dehydrogenase. The genes encoding l-phenylserine dehydrogenase and d-phenylserine dehydrogenase, which is induced by phenylserine, are located in a single operon. The reaction products of both enzymatic reactions were 2-aminoacetophenone and CO2.

  5. Anatomical changes on coffee leaves infected by Pseudomonas syringae pv. garcae

    Directory of Open Access Journals (Sweden)

    Lucas Mateus Rivero Rodrigues

    2015-12-01

    Full Text Available ABSTRACTAlthough poorly studied, the bacterial halo blight is an important disease in the major coffee-producing states of Brazil. External damage and anatomical changes on leaves were measured in seedlings of Coffea arabica cv. Mundo Novo, susceptible to Pseudomonas syringae pv. garcae, by using histological sections obtained at 10 and 20 days after inoculation (DAI. The changes on the epidermis were smaller than the lesions measured in the mesophyll, irrespective of the evaluated colonization period, showing that the internal damage caused by the bacterium represent twice the damage observed externally. From the inoculation site, lysis occurred on the epidermal cells and on the palisade and spongy parenchyma cells, with strong staining of their cellular contents, as well as abnormal intercellular spaces in the palisade parenchyma, hypertrophy and hyperplasia of mesophyll cells and partial destruction of chloroplasts. Additionally, this study revealed the presence of inclusion bodies in epidermal and mesophyll cells. Bacterial masses were found in the apoplast between and within mesophyll cells. Bacteria were also observed in the bundle sheath and vascular bundles and were more pronounced at 20 DAI, not only near the inoculation site but also in distant areas, suggesting displacement through the vascular system. These results can be useful to understand this plant-pathogen interaction.

  6. Dynamics of membrane potential variation and gene expression induced by Spodoptera littoralis, Myzus persicae, and Pseudomonas syringae in Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Irene Bricchi

    Full Text Available BACKGROUND: Biotic stress induced by various herbivores and pathogens invokes plant responses involving different defense mechanisms. However, we do not know whether different biotic stresses share a common response or which signaling pathways are involved in responses to different biotic stresses. We investigated the common and specific responses of Arabidopsis thaliana to three biotic stress agents: Spodoptera littoralis, Myzus persicae, and the pathogen Pseudomonas syringae. METHODOLOGY/PRINCIPAL FINDINGS: We used electrophysiology to determine the plasma membrane potential (V(m and we performed a gene microarray transcriptome analysis on Arabidopsis upon either herbivory or bacterial infection. V(m depolarization was induced by insect attack; however, the response was much more rapid to S. littoralis (30 min -2 h than to M. persicae (4-6 h. M. persicae differentially regulated almost 10-fold more genes than by S. littoralis with an opposite regulation. M. persicae modulated genes involved in flavonoid, fatty acid, hormone, drug transport and chitin metabolism. S. littoralis regulated responses to heat, transcription and ion transport. The latest Vm depolarization (16 h was found for P. syringae. The pathogen regulated responses to salicylate, jasmonate and to microorganisms. Despite this late response, the number of genes differentially regulated by P. syringae was closer to those regulated by S. littoralis than by M. persicae. CONCLUSIONS/SIGNIFICANCE: Arabidopsis plasma membranes respond with a V(m depolarization at times depending on the nature of biotic attack which allow setting a time point for comparative genome-wide analysis. A clear relationship between V(m depolarization and gene expression was found. At V(m depolarization timing, M. persicae regulates a wider array of Arabidopsis genes with a clear and distinct regulation than S. littoralis. An almost completely opposite regulation was observed between the aphid and the pathogen

  7. Dynamics of Membrane Potential Variation and Gene Expression Induced by Spodoptera littoralis, Myzus persicae, and Pseudomonas syringae in Arabidopsis

    Science.gov (United States)

    Bricchi, Irene; Bertea, Cinzia M.; Occhipinti, Andrea; Paponov, Ivan A.; Maffei, Massimo E.

    2012-01-01

    Background Biotic stress induced by various herbivores and pathogens invokes plant responses involving different defense mechanisms. However, we do not know whether different biotic stresses share a common response or which signaling pathways are involved in responses to different biotic stresses. We investigated the common and specific responses of Arabidopsis thaliana to three biotic stress agents: Spodoptera littoralis, Myzus persicae, and the pathogen Pseudomonas syringae. Methodology/Principal Findings We used electrophysiology to determine the plasma membrane potential (Vm) and we performed a gene microarray transcriptome analysis on Arabidopsis upon either herbivory or bacterial infection. Vm depolarization was induced by insect attack; however, the response was much more rapid to S. littoralis (30 min −2 h) than to M. persicae (4–6 h). M. persicae differentially regulated almost 10-fold more genes than by S. littoralis with an opposite regulation. M. persicae modulated genes involved in flavonoid, fatty acid, hormone, drug transport and chitin metabolism. S. littoralis regulated responses to heat, transcription and ion transport. The latest Vm depolarization (16 h) was found for P. syringae. The pathogen regulated responses to salicylate, jasmonate and to microorganisms. Despite this late response, the number of genes differentially regulated by P. syringae was closer to those regulated by S. littoralis than by M. persicae. Conclusions/Significance Arabidopsis plasma membranes respond with a Vm depolarization at times depending on the nature of biotic attack which allow setting a time point for comparative genome-wide analysis. A clear relationship between Vm depolarization and gene expression was found. At Vm depolarization timing, M. persicae regulates a wider array of Arabidopsis genes with a clear and distinct regulation than S. littoralis. An almost completely opposite regulation was observed between the aphid and the pathogen, with the former

  8. Auxin promotes susceptibility to Pseudomonas syringae via a mechanism independent of suppression of salicylic acid-mediated defenses.

    Science.gov (United States)

    Mutka, Andrew M; Fawley, Stephen; Tsao, Tiffany; Kunkel, Barbara N

    2013-06-01

    Auxin is a key plant growth regulator that also impacts plant-pathogen interactions. Several lines of evidence suggest that the bacterial plant pathogen Pseudomonas syringae manipulates auxin physiology in Arabidopsis thaliana to promote pathogenesis. Pseudomonas syringae strategies to alter host auxin biology include synthesis of the auxin indole-3-acetic acid (IAA) and production of virulence factors that alter auxin responses in host cells. The application of exogenous auxin enhances disease caused by P. syringae strain DC3000. This is hypothesized to result from antagonism between auxin and salicylic acid (SA), a major regulator of plant defenses, but this hypothesis has not been tested in the context of infected plants. We further investigated the role of auxin during pathogenesis by examining the interaction of auxin and SA in the context of infection in plants with elevated endogenous levels of auxin. We demonstrated that elevated IAA biosynthesis in transgenic plants overexpressing the YUCCA 1 (YUC1) auxin biosynthesis gene led to enhanced susceptibility to DC3000. Elevated IAA levels did not interfere significantly with host defenses, as effector-triggered immunity was active in YUC1-overexpressing plants, and we observed only minor effects on SA levels and SA-mediated responses. Furthermore, a plant line carrying both the YUC1-overexpression transgene and the salicylic acid induction deficient 2 (sid2) mutation, which impairs SA synthesis, exhibited additive effects of enhanced susceptibility from both elevated auxin levels and impaired SA-mediated defenses. Thus, in IAA overproducing plants, the promotion of pathogen growth occurs independently of suppression of SA-mediated defenses. © 2013 The Authors The Plant Journal © 2013 John Wiley & Sons Ltd.

  9. Expression of antimicrobial peptides under control of a camalexin-biosynthetic promoter confers enhanced resistance against Pseudomonas syringae.

    Science.gov (United States)

    Chapman, Alexandra; Lindermayr, Christian; Glawischnig, Erich

    2016-02-01

    In Arabidopsis thaliana phytoalexin biosynthesis is tightly regulated. The camalexin biosynthetic gene CYP71B15/PAD3 is highly expressed in response to pathogens and specific abiotic triggers, while constitutive expression is very low. Based on this property we expressed artificial antimicrobial peptides under control of the CYP71B15 promoter avoiding potential toxic effects to the plant related to constitutive expression. Significant and substantial growth inhibition of Pseudomonas syringae was observed, demonstrating that expression of these peptides under control of a phytoalexin promoter is an effective approach for enhancement of resistance against bacterial pathogens. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. [Molecular genetic marker-based approaches to the verification of lilac Syringa vulgaris L. in in vitro collections].

    Science.gov (United States)

    Mel'nikova, N V; Borkhert, E V; Martynov, S P; Okuneva, I B; Molkanova, O I; Upelniek, V P; Kudriavtsev, A M

    2009-01-01

    RAPD analysis was used to verify the varieties in an in vitro germplasm collection of lilac Syringa vulgaris L. RAPD patterns were obtained with 16 decanucleotide primers for 46 accessions (microclones and corresponding reference varieties). The RAPD patterns of a microclone and the corresponding reference variety often differed in composition; consequently, it was infeasible to verify the accessions by direct comparison of the RAPD patterns. Hence, evaluation of the relative genetic distances between accessions (microclones) and known varieties was proposed as a method to verify lilac in vitro germplasm collections.

  11. Adaptation of the pathogen, Pseudomonas syringae, during experimental evolution on a native vs. alternative host plant.

    Science.gov (United States)

    Meaden, Sean; Koskella, Britt

    2017-04-01

    The specialization and distribution of pathogens among species has substantial impact on disease spread, especially when reservoir hosts can maintain high pathogen densities or select for increased pathogen virulence. Theory predicts that optimal within-host growth rate will vary among host genotypes/species and therefore that pathogens infecting multiple hosts should experience different selection pressures depending on the host environment in which they are found. This should be true for pathogens with broad host ranges, but also those experiencing opportunistic infections on novel hosts or that spill over among host populations. There is very little empirical data, however, regarding how adaptation to one host might directly influence infectivity and growth on another. We took an experimental evolution approach to examine short-term adaptation of the plant pathogen, Pseudomonas syringae pathovar tomato, to its native tomato host compared with an alternative host, Arabidopsis, in either the presence or absence of bacteriophages. After four serial passages (20 days of selection in planta), we measured bacterial growth of selected lines in leaves of either the focal or alternative host. We found that passage through Arabidopsis led to greater within-host bacterial densities in both hosts than did passage through tomato. Whole genome resequencing of evolved isolates identified numerous single nucleotide polymorphisms based on our novel draft assembly for strain PT23. However, there was no clear pattern of clustering among plant selection lines at the genetic level despite the phenotypic differences observed. Together, the results emphasize that previous host associations can influence the within-host growth rate of pathogens. © 2017 The Authors. Molecular Ecology Published by John Wiley & Sons Ltd.

  12. Controlled ice nucleation using freeze-dried Pseudomonas syringae encapsulated in alginate beads.

    Science.gov (United States)

    Weng, Lindong; Tessier, Shannon N; Swei, Anisa; Stott, Shannon L; Toner, Mehmet

    2017-04-01

    The control of ice nucleation is of fundamental significance in many process technologies related to food and pharmaceutical science and cryobiology. Mechanical perturbation, electromagnetic fields and ice-nucleating agents (INAs) have been known to induce ice nucleation in a controlled manner. But these ice-nucleating methods may suffer from cumbersome manual operations, safety concerns of external fields, and biocompatibility and recovery issues of INA particles, especially when used in living systems. Given the automatic ice-seeding nature of INAs, a promising solution to overcome some of the above limitations is to engineer a biocomposite that accommodates the INA particles but minimizes their interactions with biologics, as well as enabling the recovery of used particles. In this study, freeze-dried Pseudomonas syringae, a model ice-nucleating agent, was encapsulated into microliter-sized alginate beads. We evaluated the performance of the bacterial hydrogel beads to initiate ice nucleation in water and aqueous glycerol solution by investigating factors including the size and number of the beads and the local concentration of INA particles. In the aqueous sample of a fixed volume, the total mass of the INA particles (m) was found to be the governing parameter that is solely responsible for determining the ice nucleation performance of the bacterial hydrogel beads. The freezing temperature has a strong positive linear correlation with log 10 m. The findings in this study provide an effective, predictable approach to control ice nucleation, which can improve the outcome and standardization of many ice-assisted process technologies. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Genome-Wide Analysis of Chromatin Accessibility in Arabidopsis Infected with Pseudomonas syringae.

    Science.gov (United States)

    Bordiya, Yogendra; Kang, Hong-Gu

    2017-01-01

    Changes in chromatin accessibility are an important aspect of the molecular changes that occur in eukaryotic cells responding to stress, and they appear to play a critical role in stress-induced transcriptional activation/reprogramming and epigenetic changes. In plants, pathogen infection has been shown to induce rapid and drastic transcriptional reprogramming; growing evidence suggests that chromatin remodeling plays an essential role in this phenomenon. The recent development of genomic tools to assess chromatin accessibility presents a significant opportunity to investigate the relationship between chromatin dynamicity and gene expression. In this protocol, we have adopted a popular chromatin accessibility assay, DNase-seq, to measure chromatin accessibility in Arabidopsis infected with the bacterial pathogen Pseudomonas syringae pv. tomato (Pst). DNase-seq provides information on chromatin accessibility through the sequencing of DNA fragments generated by DNase I digestion of open chromatin, followed by mapping these sequences on a reference genome. Of the two popular DNase-seq approaches, we based our method on the Stamatoyannopoulos protocol, which involves two DNase cleavages rather than a single cleavage, followed by size fractionation. Please note that this two-cleavage approach is widely accepted and has been used extensively by ENCODE (Encyclopedia of DNA Elements) project, a public research consortium investigating cis- and trans-elements in the transcriptional regulation in animal cells. To enhance the quality of the chromatin accessibility assay, we modified this protocol by including two centrifugation steps for nuclear enrichment and size fractionation and an extra washing step for removal of chloroplasts and Pst. The outcomes obtained by this approach are also discussed.

  14. Dissection of Resistance Genes to Pseudomonas syringae pv. phaseolicola in UI3 Common Bean Cultivar

    Directory of Open Access Journals (Sweden)

    Ana M. González

    2017-11-01

    Full Text Available Few quantitative trait loci have been mapped for resistance to Pseudomonas syringae pv. phaseolicola in common bean. Two F2 populations were developed from the host differential UI3 cultivar. The objective of this study was to further characterize the resistance to races 1, 5, 7 and 9 of Psp included in UI3. Using a QTL mapping approach, 16 and 11 main-effect QTLs for pod and primary leaf resistance were located on LG10, explaining up to 90% and 26% of the phenotypic variation, respectively. The homologous genomic region corresponding to primary leaf resistance QTLs detected tested positive for the presence of resistance-associated gene cluster encoding nucleotide-binding and leucine-rich repeat (NL, Natural Resistance Associated Macrophage (NRAMP and Pentatricopeptide Repeat family (PPR proteins. It is worth noting that the main effect QTLs for resistance in pod were located inside a 3.5 Mb genomic region that included the Phvul.010G021200 gene, which encodes a protein that has the highest sequence similarity to the RIN4 gene of Arabidopsis, and can be considered an important candidate gene for the organ-specific QTLs identified here. These results support that resistance to Psp from UI3 might result from the immune response activated by combinations of R proteins, and suggest the guard model as an important mechanism in pod resistance to halo blight. The candidate genes identified here warrant functional studies that will help in characterizing the actual defense gene(s in UI3 genotype.

  15. Development of a Multiple Loci Variable Number of Tandem Repeats Analysis (MLVA) to Unravel the Intra-Pathovar Structure of Pseudomonas syringae pv. actinidiae Populations Worldwide

    Science.gov (United States)

    Ciarroni, Serena; Gallipoli, Lorenzo; Taratufolo, Maria C.; Butler, Margi I.; Poulter, Russell T. M.; Pourcel, Christine; Vergnaud, Gilles; Balestra, Giorgio M.; Mazzaglia, Angelo

    2015-01-01

    The bacterial canker of kiwifruit by Pseudomonas syringae pv. actinidiae is an emblematic example of a catastrophic disease of fruit crops. In 2008 a new, extremely virulent form of the pathogen emerged and rapidly devastated many Actinidia spp. orchards all over the world. In order to understand differences in populations within this pathovar and to elucidate their diffusion and movements on world scale, it is necessary to be able to quickly and on a routine basis compare new isolates with previous records. In this report a worldwide collection of 142 strains was analyzed by MLVA, chosen as investigative technique for its efficacy, reproducibility, simplicity and low cost. A panel of 13 Variable Number of Tandem Repeats (VNTR) loci was identified and used to describe the pathogen population. The MLVA clustering is highly congruent with the population structure as previously established by other molecular approaches including whole genome sequencing and correlates with geographic origin, time of isolation and virulence. For convenience, we divided the VNTR loci in two panels. Panel 1 assay, using six loci, recognizes 23 different haplotypes, clustered into ten complexes with highest congruence with previous classifications. Panel 2, with seven VNTR loci, provides discriminatory power. Using the total set of 13 VNTR loci, 58 haplotypes can be distinguished. The recent hypervirulent type shows very limited diversity and includes, beside the strains from Europe, New Zealand and Chile, a few strains from Shaanxi, China. A broad genetic variability is observed in China, but different types are also retrievable in Japan and Korea. The low virulent strains cluster together and are very different from the other MLVA genotypes. Data were used to generate a public database in MLVAbank. MLVA represents a very promising first-line assay for large-scale routine genotyping, prior to whole genome sequencing of only the most relevant samples. PMID:26262683

  16. Assessment of strains of Pseudomonas syringae pv. tomato from Tanzania for resistance to copper and streptomycin

    DEFF Research Database (Denmark)

    Shenge, K.C.; Wydra, K.; Mabagala, M.B.

    2008-01-01

    Fifty-six strains of Pseudomonas syringae pv. tomato (P.s. pv. tomato) were collected from tomato-producing areas in Tanzania and assessed for resistance to copper and antibiotics. The collection was done from three tomato-producing regions (Morogoro, Arusha and Iringa), representing three differ...

  17. The Arabidopsis thaliana lectin receptor kinase LecRK-I.9 is required for full resistance to Pseudomonas syringae and affects jasmonate signalling.

    Science.gov (United States)

    Balagué, Claudine; Gouget, Anne; Bouchez, Olivier; Souriac, Camille; Haget, Nathalie; Boutet-Mercey, Stéphanie; Govers, Francine; Roby, Dominique; Canut, Hervé

    2017-09-01

    On microbial attack, plants can detect invaders and activate plant innate immunity. For the detection of pathogen molecules or cell wall damage, plants employ receptors that trigger the activation of defence responses. Cell surface proteins that belong to large families of lectin receptor kinases are candidates to function as immune receptors. Here, the function of LecRK-I.9 (At5g60300), a legume-type lectin receptor kinase involved in cell wall-plasma membrane contacts and in extracellular ATP (eATP) perception, was studied through biochemical, gene expression and reverse genetics approaches. In Arabidopsis thaliana, LecRK-I.9 expression is rapidly, highly and locally induced on inoculation with avirulent strains of Pseudomonas syringae pv. tomato (Pst). Two allelic lecrk-I.9 knock-out mutants showed decreased resistance to Pst. Conversely, over-expression of LecRK-I.9 led to increased resistance to Pst. The analysis of defence gene expression suggests an alteration of both the salicylic acid (SA) and jasmonic acid (JA) signalling pathways. In particular, LecRK-I.9 expression during plant-pathogen interaction was dependent on COI1 (CORONATINE INSENSITIVE 1) and JAR1 (JASMONATE RESISTANT 1) components, and JA-responsive transcription factors (TFs) showed altered levels of expression in plants over-expressing LecRK-I.9. A similar misregulation of these TFs was obtained by JA treatment. This study identified LecRK-I.9 as necessary for full resistance to Pst and demonstrated its involvement in the control of defence against pathogens through a regulation of JA signalling components. The role of LecRK-I.9 is discussed with regard to the potential molecular mechanisms linking JA signalling to cell wall damage and/or eATP perception. © 2016 BSPP AND JOHN WILEY & SONS LTD.

  18. The Arabidopsis lectin receptor kinase LecRK-V.5 represses stomatal immunity induced by Pseudomonas syringae pv. tomato DC3000.

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    Marie Desclos-Theveniau

    2012-02-01

    Full Text Available Stomata play an important role in plant innate immunity by limiting pathogen entry into leaves but molecular mechanisms regulating stomatal closure upon pathogen perception are not well understood. Here we show that the Arabidopsis thaliana L-type lectin receptor kinase-V.5 (LecRK-V.5 negatively regulates stomatal immunity. Loss of LecRK-V.5 function increased resistance to surface inoculation with virulent bacteria Pseudomonas syringae pv tomato DC3000. Levels of resistance were not affected after infiltration-inoculation, suggesting that LecRK-V.5 functions at an early defense stage. By contrast, lines overexpressing LecRK-V.5 were more susceptible to Pst DC3000. Enhanced resistance in lecrk-V.5 mutants was correlated with constitutive stomatal closure, while increased susceptibility phenotypes in overexpression lines were associated with early stomatal reopening. Lines overexpressing LecRK-V.5 also demonstrated a defective stomatal closure after pathogen-associated molecular pattern (PAMP treatments. LecRK-V.5 is rapidly expressed in stomatal guard cells after bacterial inoculation or treatment with the bacterial PAMP flagellin. In addition, lecrk-V.5 mutants guard cells exhibited constitutive accumulation of reactive oxygen species (ROS and inhibition of ROS production opened stomata of lecrk-V.5. LecRK-V.5 is also shown to interfere with abscisic acid-mediated stomatal closure signaling upstream of ROS production. These results provide genetic evidences that LecRK-V.5 negatively regulates stomatal immunity upstream of ROS biosynthesis. Our data reveal that plants have evolved mechanisms to reverse bacteria-mediated stomatal closure to prevent long-term effect on CO(2 uptake and photosynthesis.

  19. Overexpression of Nictaba-Like Lectin Genes from Glycine max Confers Tolerance towards Pseudomonas syringae Infection, Aphid Infestation and Salt Stress in Transgenic Arabidopsis Plants

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    Sofie Van Holle

    2016-10-01

    Full Text Available Plants have evolved a sophisticated immune system that allows them to recognize invading pathogens by specialized receptors. Carbohydrate-binding proteins or lectins are part of this immune system and especially the lectins that reside in the nucleocytoplasmic compartment are known to be implicated in biotic and abiotic stress responses. The class of Nictaba-like lectins (NLL groups all proteins with homology to the tobacco (Nicotiana tabacum lectin, known as a stress-inducible lectin. Here we focus on two Nictaba homologs from soybean (Glycine max, referred to as GmNLL1 and GmNLL2. Confocal laser scanning microscopy of fusion constructs with the green fluorescent protein either transiently expressed in Nicotiana benthamiana leaves or stably transformed in tobacco BY-2 suspension cells revealed a nucleocytoplasmic localization for the GmNLLs under study. RT-qPCR analysis of the transcript levels for the Nictaba-like lectins in soybean demonstrated that the genes are expressed in several tissues throughout the development of the plant. Furthermore, it was shown that salt treatment, Phytophthora sojae infection and Aphis glycines infestation trigger the expression of particular NLL genes. Stress experiments with Arabidopsis lines overexpressing the NLLs from soybean yielded an enhanced tolerance of the plant towards bacterial infection (Pseudomonas syringae, insect infestation (Myzus persicae and salinity. Our data showed a better performance of the transgenic lines compared to wild type plants, indicating that the NLLs from soybean are implicated in the stress response. These data can help to further elucidate the physiological importance of the Nictaba-like lectins from soybean, which can ultimately lead to the design of crop plants with a better tolerance to changing environmental conditions.

  20. [Increased Size of Epidermal Cells in Syringa josikaea Jacq. Smaller Leaf Side as an Adaptive Mechanism for Reducing Its Asymmetry].

    Science.gov (United States)

    Polonskii, V I; Polyakova, I S

    2015-01-01

    Comparative study of quantitative anatomy of the epidermis in Syringa josikaea Jacq. leaf halves of different width was conducted in order to analyze the possible mechanism of formation of the value of fluctuating leaf asymmetry. A regular decrease in the density of main epidermal cells in the smaller leaf half compared with the bigger one was traced during leaf ontogeny. Stomatal index was equal in different-sized leaf halves. Adaptive response was found in fully formed leaves; it was aimed at reducing leaf blade fluctuating asymmetry by 23% on average and consisted of compensatory growth--further elongation of main epidermal cells in the smaller half of the leaf. It was concluded that the level of fluctuating leaf asymmetry in Hungary lilac is mainly due to a lower rate of cell division, as well as due to their greater elongation in the smaller half of adult leaf compared with the bigger half.

  1. Sources of resistance to races R0 and R1 of Pseudomonas syringae PV. tomato - agent of bacterial speck on tomato

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    Ganeva Daniela

    2017-01-01

    Full Text Available Tomato breeding lines with fruit colour different from the traditional red colour were studied in order to search for sources of resistance to races R0 and R1 of Pseudomonas syringae pv. tomato. As a result of selection of healthy plants with hypersensitive response (HR, the resistance was stabilized and perspective lines gene-carriers of resistance to bacterial speck were chosen. Lines L1078 and L1083 with brown-red (black coloured fruits and line L1130 with purple-red fruits possess a complex resistance to races R0 and R1. It was established that two of the lines with rose-coloured tomato fruits (L1088 and L584 were resistant to race 1 of P. syringae pv. tomato. These lines possessed valuable economic and morphological characters and they could be used in combinative and heterosis breeding for development of resistance to bacterial speck varieties.

  2. One shot-two pathogens blocked: exposure of Arabidopsis to hexadecane, a long chain volatile organic compound, confers induced resistance against both Pectobacterium carotovorum and Pseudomonas syringae.

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    Park, Hyo Bee; Lee, Boyoung; Kloepper, Joseph W; Ryu, Choong-Min

    2013-07-01

    Bacteria and plant derived volatile organic compounds have been reported as the chemical triggers that elicit induced resistance in plants. Previously, volatile organic compounds (VOCs), including acetoin and 2,3-butanediol, were found to be emitted from plant growth-promoting rhizobacteria (PGPR) Bacillus subtilis GB03, which had been shown to elicit ISR and plant growth promotion. More recently, we reported data that stronger induced resistance could be elicited against Pseudomonas syringae pv maculicola ES4326 in plants exposed to C13 VOC from another PGPR Paenibacillus polymyxa E681 compared with that of strain GB03. Here, we assessed whether another long hydrocarbon C16 hexadecane (HD) conferred protection to Arabidopsis from infection of a biotrophic pathogen, P. syringae pv maculicola and a necrotrophic pathogen, Pectobacterium carotovorum subsp carotovorum. Collectively, long-chain VOCs can be linked to a plant resistance activator for protecting plants against both biotrophic and necrotrophic pathogens at the same time.

  3. HPLC-NNE13CNMR coupling fingerprint analysis technology and its application in a study of Syringa pubescens Turcz and its activity against hepatic fibrosis

    OpenAIRE

    Zhang ZX; Yin WP; Liu P; Zhao TZ

    2013-01-01

    Zhixin Zhang,1 Weiping Yin,1 Pu Liu,1 Tianzeng Zhao2 1School of Chemical Engineering and Pharmaceutics, Henan University of Science and Technology, Luoyang, People’s Republic of China; 2Key Laboratory of Natural Products, Henan Academy of Sciences, Zhengzhou, People's Republic of China Abstract: This study describes the active ingredients of Syringa pubescens Turcz which has been identified as being able to protect against hepatic fibrosis. Here we report the characteristic...

  4. Identification of Pseudomonas syringae pv. actinidiae strains causing bacterial canker of kiwifruit in the Anhui Province of China, and determination of their streptomycin sensitivities.

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    Yang, X; Yi, X-K; Chen, Y; Zhang, A-F; Zhang, J-Y; Gao, Z-H; Qi, Y-J; Xu, Y-L

    2015-07-27

    Bacterial canker, caused by Pseudomonas syringae pv. actinidiae, is one of the most severe diseases of kiwifruit. It has become an international pandemic and threatens the sustainable development of kiwifruit production in all main kiwi-growing regions worldwide. Streptomycin has been the major bactericide for the control of kiwifruit canker, especially in Anhui Province, one of the main kiwifruit production regions in China. However, until now, no studies on the baseline sensitivity to streptomycin of field isolates of P. syringae pv. actinidiae from China have been available. During 2012-2013, a total of 102 single-colony P. syringae pv. actinidiae strains were isolated: 36, 12, 13, 26, and 15 strains from Yuexi, Jinzhai, Huoshan, Qianshan, and Taihu counties, respectively. All strains were confirmed by production of a 280-bp fragment using the specific primers PsaF1/R2 upon polymerase chain reaction amplification, followed by an assay for confirmation of pathogenicity to fulfill Koch's postulates. In this study, the streptomycin sensitivity of the 102 isolated strains was determined. The half-maximal effective concentration values for inhibition of growth by streptomycin were 0.03-0.42 μg/mL (average 0.12 ± 0.06 μg/mL). The baseline sensitivity curve was unimodal, representing range-of-variation factors of 14.0. No resistant subpopulation was identified among the strains used in the study. Thus, these sensitivity data could be used as a baseline for monitoring the shift in sensitivity of P. syringae pv. actinidiae populations to streptomycin in Anhui Province. Continuous resistance monitoring should be carried out, as streptomycin is an at-risk bactericide agent.

  5. Arabidopsis CaM binding protein CBP60g contributes to MAMP-induced SA accumulation and is involved in disease resistance against Pseudomonas syringae.

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    Lin Wang

    2009-02-01

    Full Text Available Salicylic acid (SA-induced defense responses are important factors during effector triggered immunity and microbe-associated molecular pattern (MAMP-induced immunity in plants. This article presents evidence that a member of the Arabidopsis CBP60 gene family, CBP60g, contributes to MAMP-triggered SA accumulation. CBP60g is inducible by both pathogen and MAMP treatments. Pseudomonas syringae growth is enhanced in cbp60g mutants. Expression profiles of a cbp60g mutant after MAMP treatment are similar to those of sid2 and pad4, suggesting a defect in SA signaling. Accordingly, cbp60g mutants accumulate less SA when treated with the MAMP flg22 or a P. syringae hrcC strain that activates MAMP signaling. MAMP-induced production of reactive oxygen species and callose deposition are unaffected in cbp60g mutants. CBP60g is a calmodulin-binding protein with a calmodulin-binding domain located near the N-terminus. Calmodulin binding is dependent on Ca(2+. Mutations in CBP60g that abolish calmodulin binding prevent complementation of the SA production and bacterial growth defects of cbp60g mutants, indicating that calmodulin binding is essential for the function of CBP60g in defense signaling. These studies show that CBP60g constitutes a Ca(2+ link between MAMP recognition and SA accumulation that is important for resistance to P. syringae.

  6. Variation in extragenic repetitive DNA sequences in Pseudomonas syringae and potential use of modified REP primers in the identification of closely related isolates

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    Elif Çepni

    2012-01-01

    Full Text Available In this study, Pseudomonas syringe pathovars isolated from olive, tomato and bean were identified by species-specific PCR and their genetic diversity was assessed by repetitive extragenic palindromic (REP-PCR. Reverse universal primers for REP-PCR were designed by using the bases of A, T, G or C at the positions of 1, 4 and 11 to identify additional polymorphism in the banding patterns. Binding of the primers to different annealing sites in the genome revealed additional fingerprint patterns in eight isolates of P. savastanoi pv. savastanoi and two isolates of P. syringae pv. tomato. The use of four different bases in the primer sequences did not affect the PCR reproducibility and was very efficient in revealing intra-pathovar diversity, particularly in P. savastanoi pv. savastanoi. At the pathovar level, the primer BOX1AR yielded shared fragments, in addition to five bands that discriminated among the pathovars P. syringae pv. phaseolicola, P. savastanoi pv. savastanoi and P. syringae pv. tomato. REP-PCR with a modified primer containing C produced identical bands among the isolates in a pathovar but separated three pathovars more distinctly than four other primers. Although REP-and BOX-PCRs have been successfully used in the molecular identification of Pseudomonas isolates from Turkish flora, a PCR based on inter-enterobacterial repetitive intergenic concensus (ERIC sequences failed to produce clear banding patterns in this study.

  7. HPLC-NNE13CNMR coupling fingerprint analysis technology and its application in a study of Syringa pubescens Turcz and its activity against hepatic fibrosis

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    Zhang ZX

    2013-07-01

    Full Text Available Zhixin Zhang,1 Weiping Yin,1 Pu Liu,1 Tianzeng Zhao2 1School of Chemical Engineering and Pharmaceutics, Henan University of Science and Technology, Luoyang, People’s Republic of China; 2Key Laboratory of Natural Products, Henan Academy of Sciences, Zhengzhou, People's Republic of China Abstract: This study describes the active ingredients of Syringa pubescens Turcz which has been identified as being able to protect against hepatic fibrosis. Here we report the characteristics of high performance liquid chromatography and non-nuclear overhauser effect carbon-13 nuclear magnetic resonance (HPLC-NNE13CNMR technology developed for coupling fingerprint analysis. The major contribution of this new method is the development of an efficient technology and a useful tool for analysis of a traditional Chinese herbal medicine using chromatography and spectral coupling fingerprint technology. Isolation of secoiridoid glycosides and investigation of their structure-activity relationship showed that these derivatives are the active ingredients of Syringa pubescens Turcz, and account for the activity of this plant against hepatic fibrosis. The active compounds were identified as oleuropein, 10-hydroxyoleuropein, oleoside-11-methylester, (8Z-ligstroside, and echinacoside by HPLC-NNE13CNMR coupling fingerprint analysis. A concentration-response relationship was also demonstrated for the HPLC-NNE13CNMR coupling fingerprint method. Keywords: HPLC-NNE13CNMR, coupling fingerprint, hepatic fibrosis, Syringa pubescens Turcz, analysis technology

  8. Mutations in LACS2, a Long-Chain Acyl-Coenzyme A Synthetase, Enhance Susceptibility to Avirulent Pseudomonas syringae But Confer Resistance to Botrytis cinerea in Arabidopsis1[OA

    Science.gov (United States)

    Tang, Dingzhong; Simonich, Michael T.; Innes, Roger W.

    2007-01-01

    We identified an Arabidopsis (Arabidopsis thaliana) mutant, sma4 (symptoms to multiple avr genotypes4), that displays severe disease symptoms when inoculated with avirulent strains of Pseudomonas syringae pv tomato, although bacterial growth is only moderately enhanced compared to wild-type plants. The sma4 mutant showed a normal susceptible phenotype to the biotrophic fungal pathogen Erysiphe cichoracearum. Significantly, the sma4 mutant was highly resistant to a necrotrophic fungal pathogen, Botrytis cinerea. Germination of B. cinerea spores on sma4 mutant leaves was inhibited, and penetration by those that did germinate was rare. The sma4 mutant also showed several pleiotropic phenotypes, including increased sensitivity to lower humidity and salt stress. Isolation of SMA4 by positional cloning revealed that it encodes LACS2, a member of the long-chain acyl-CoA synthetases. LACS2 has previously been shown to be involved in cutin biosynthesis. We therefore tested three additional cutin-defective mutants for resistance to B. cinerea: att1 (for aberrant induction of type three genes), bodyguard, and lacerata. All three displayed an enhanced resistance to B. cinerea. Our results indicate that plant cutin or cuticle structure may play a crucial role in tolerance to biotic and abiotic stress and in the pathogenesis of B. cinerea. PMID:17434992

  9. The Identification of Genes Important in Pseudomonas syringae pv. phaseolicola Plant Colonisation Using In Vitro Screening of Transposon Libraries.

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    Bharani Manoharan

    Full Text Available The bacterial plant pathogen Pseudomonas syringae pv. phaseolicola (Pph colonises the surface of common bean plants before moving into the interior of plant tissue, via wounds and stomata. In the intercellular spaces the pathogen proliferates in the apoplastic fluid and forms microcolonies (biofilms around plant cells. If the pathogen can suppress the plant's natural resistance response, it will cause halo blight disease. The process of resistance suppression is fairly well understood, but the mechanisms used by the pathogen in colonisation are less clear. We hypothesised that we could apply in vitro genetic screens to look for changes in motility, colony formation, and adhesion, which are proxies for infection, microcolony formation and cell adhesion. We made transposon (Tn mutant libraries of Pph strains 1448A and 1302A and found 106/1920 mutants exhibited alterations in colony morphology, motility and biofilm formation. Identification of the insertion point of the Tn identified within the genome highlighted, as expected, a number of altered motility mutants bearing mutations in genes encoding various parts of the flagellum. Genes involved in nutrient biosynthesis, membrane associated proteins, and a number of conserved hypothetical protein (CHP genes were also identified. A mutation of one CHP gene caused a positive increase in in planta bacterial growth. This rapid and inexpensive screening method allows the discovery of genes important for in vitro traits that can be correlated to roles in the plant interaction.

  10. JMJ27, an Arabidopsis H3K9 histone demethylase, modulates defense against Pseudomonas syringae and flowering time.

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    Dutta, Aditya; Choudhary, Pratibha; Caruana, Julie; Raina, Ramesh

    2017-09-01

    Histone methylation is known to dynamically regulate diverse developmental and physiological processes. Histone methyl marks are written by methyltransferases and erased by demethylases, and result in modification of chromatin structure to repress or activate transcription. However, little is known about how histone methylation may regulate defense mechanisms and flowering time in plants. Here we report characterization of JmjC DOMAIN-CONTAINING PROTEIN 27 (JMJ27), an Arabidopsis JHDM2 (JmjC domain-containing histone demethylase 2) family protein, which modulates defense against pathogens and flowering time. JMJ27 is a nuclear protein containing a zinc-finger motif and a catalytic JmjC domain with conserved Fe(II) and α-ketoglutarate binding sites, and displays H3K9me1/2 demethylase activity both in vitro and in vivo. JMJ27 is induced in response to virulent Pseudomonas syringae pathogens and is required for resistance against these pathogens. JMJ27 is a negative modulator of WRKY25 (a repressor of defense) and a positive modulator of several pathogenesis-related (PR) proteins. Additionally, loss of JMJ27 function leads to early flowering. JMJ27 negatively modulates the major flowering regulator CONSTANS (CO) and positively modulates FLOWERING LOCUS C (FLC). Taken together, our results indicate that JMJ27 functions as a histone demethylase to modulate both physiological (defense) and developmental (flowering time) processes in Arabidopsis. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.

  11. Pollen as a possible pathway for the dissemination of Pseudomonas syringae pv. actinide and bacterial canker of kiwifruit

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    Rodanthi TONTOU

    2014-09-01

    Full Text Available Pollen collected in a kiwifruit orchard with symptoms of bacterial canker and naturally contaminated by Pseudomonas syringae pv. actinidiae (Psa, was used to pollinate an experimental orchard, in order to confirm its role, under commercial orchard conditions, in disseminating the pathogen and, possibly, contributing to disease spread. A pollen lot, certified free from Psa, was used with the same methods as a control. Two pollination techniques were used: dusting (dry pollen and spraying (pollen suspension in water. The orchard was monitored during 2 years from experimental pollination, with regular sampling of flowers, fruits, leaves, and vines, to check for Psa as an epiphyte or endophyte, and for bacterial canker symptoms. Psa was recovered from flowers, fruitlets and leaves during the first season, mainly in plots where contaminated pollen had been sprayed in water suspension. From early August until harvesting time (mid-October, Psa detection was possible only on leaves. No symptoms developed during the first season after pollination. No endophytic Psa was detected in pruned vines in the following winter. During the second season, detection and isolation of Psa was erratic, but direct isolation was achieved from four plots. During the second season after pollination, typical leaf symptoms were observed on a few vines, and Psa was isolated and identified. Our results suggest that Psa could be disseminated via contaminated kiwifruit pollen as a pathway for spread of bacterial canker. However, further pollination experiments are needed to establish, beyond any doubt, whether contaminated pollen may contribute to possible disease outbreaks.

  12. The kiwifruit emerging pathogen Pseudomonas syringae pv. actinidiae does not produce AHLs but possesses three luxR solos.

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    Patel, Hitendra Kumar; Ferrante, Patrizia; Covaceuszach, Sonia; Lamba, Doriano; Scortichini, Marco; Venturi, Vittorio

    2014-01-01

    Pseudomonas syringae pv. actinidiae (Psa) is an emerging phytopathogen causing bacterial canker disease in kiwifruit plants worldwide. Quorum sensing (QS) gene regulation plays important roles in many different bacterial plant pathogens. In this study we analyzed the presence and possible role of N-acyl homoserine lactone (AHL) quorum sensing in Psa. It was established that Psa does not produce AHLs and that a typical complete LuxI/R QS system is absent in Psa strains. Psa however possesses three putative luxR solos designated here as PsaR1, PsaR2 and PsaR3. PsaR2 belongs to the sub-family of LuxR solos present in many plant associated bacteria (PAB) that binds and responds to yet unknown plant signal molecules. PsaR1 and PsaR3 are highly similar to LuxRs which bind AHLs and are part of the canonical LuxI/R AHL QS systems. Mutation in all the three luxR solos of Psa showed reduction of in planta survival and also showed additive effect if more than one solo was inactivated in double mutants. Gene promoter analysis revealed that the three solos are not auto-regulated and investigated their possible role in several bacterial phenotypes.

  13. Effects of stomatal development on stomatal conductance and on stomatal limitation of photosynthesis in Syringa oblata and Euonymus japonicus Thunb.

    Science.gov (United States)

    Wu, Bing-Jie; Chow, Wah Soon; Liu, Yu-Jun; Shi, Lei; Jiang, Chuang-Dao

    2014-12-01

    During leaf development, the increase in stomatal conductance cannot meet photosynthetic demand for CO2, thus leading to stomatal limitation of photosynthesis (Ls). Considering the crucial influences of stomatal development on stomatal conductance, we speculated whether stomatal development limits photosynthesis to some extent. To test this hypothesis, stomatal development, stomatal conductance and photosynthesis were carefully studied in both Syringa oblata (normal greening species) and Euonymus japonicus Thunb (delayed greening species). Our results show that the size of stomata increased gradually with leaf expansion, resulting in increased stomatal conductance up to the time of full leaf expansion. During this process, photosynthesis also increased steadily. Compared to that in S. oblata, the development of chloroplasts in E. japonicus Thunb was obviously delayed, leading to a delay in the improvement of photosynthetic capacity. Further analysis revealed that before full leaf expansion, stomatal limitation increased rapidly in both S. oblata and E. japonicus Thunb; after full leaf expansion, stomatal limitation continually increased in E. japonicus Thunb. Accordingly, we suggested that the enhancement of photosynthetic capacity is the main factor leading to stomatal limitation during leaf development but that stomatal development can alleviate stomatal limitation with the increase of photosynthesis by controlling gas exchange. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  14. Elicitation of Induced Resistance against Pectobacterium carotovorum and Pseudomonas syringae by Specific Individual Compounds Derived from Native Korean Plant Species

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    Choong-Min Ryu

    2013-10-01

    Full Text Available Plants have developed general and specific defense mechanisms for protection against various enemies. Among the general defenses, induced resistance has distinct characteristics, such as broad-spectrum resistance and long-lasting effectiveness. This study evaluated over 500 specific chemical compounds derived from native Korean plant species to determine whether they triggered induced resistance against Pectobacterium carotovorum supsp. carotovorum (Pcc in tobacco (Nicotiana tabacum and Pseudomonas syringae pv. tomato (Pst in Arabidopsis thaliana. To select target compound(s with direct and indirect (volatile effects, a new Petri-dish-based in vitro disease assay system with four compartments was developed. The screening assay showed that capsaicin, fisetin hydrate, jaceosidin, and farnesiferol A reduced the disease severity significantly in tobacco. Of these four compounds, capsaicin and jaceosidin induced resistance against Pcc and Pst, which depended on both salicylic acid (SA and jasmonic acid (JA signaling, using Arabidopsis transgenic and mutant lines, including npr1 and NahG for SA signaling and jar1 for JA signaling. The upregulation of the PR2 and PDF1.2 genes after Pst challenge with capsaicin pre-treatment indicated that SA and JA signaling were primed. These results demonstrate that capsaicin and jaceosidin can be effective triggers of strong induced resistance against both necrotrophic and biotrophic plant pathogens.

  15. Elicitation of induced resistance against Pectobacterium carotovorum and Pseudomonas syringae by specific individual compounds derived from native Korean plant species.

    Science.gov (United States)

    Song, Geun Cheol; Ryu, Shi Yong; Kim, Young Sup; Lee, Ji Young; Choi, Jung Sup; Ryu, Choong-Min

    2013-10-16

    Plants have developed general and specific defense mechanisms for protection against various enemies. Among the general defenses, induced resistance has distinct characteristics, such as broad-spectrum resistance and long-lasting effectiveness. This study evaluated over 500 specific chemical compounds derived from native Korean plant species to determine whether they triggered induced resistance against Pectobacterium carotovorum supsp. carotovorum (Pcc) in tobacco (Nicotiana tabacum) and Pseudomonas syringae pv. tomato (Pst) in Arabidopsis thaliana. To select target compound(s) with direct and indirect (volatile) effects, a new Petri-dish-based in vitro disease assay system with four compartments was developed. The screening assay showed that capsaicin, fisetin hydrate, jaceosidin, and farnesiferol A reduced the disease severity significantly in tobacco. Of these four compounds, capsaicin and jaceosidin induced resistance against Pcc and Pst, which depended on both salicylic acid (SA) and jasmonic acid (JA) signaling, using Arabidopsis transgenic and mutant lines, including npr1 and NahG for SA signaling and jar1 for JA signaling. The upregulation of the PR2 and PDF1.2 genes after Pst challenge with capsaicin pre-treatment indicated that SA and JA signaling were primed. These results demonstrate that capsaicin and jaceosidin can be effective triggers of strong induced resistance against both necrotrophic and biotrophic plant pathogens.

  16. Biogenetic studies in Syringa vulgaris L.: synthesis and bioconversion of deuterium-labeled precursors into lilac aldehydes and lilac alcohols.

    Science.gov (United States)

    Kreck, Mirjam; Püschel, Susen; Wüst, Matthias; Mosandl, Armin

    2003-01-15

    Syringa vulgaris L. inflorescences were fed with aqueous solutions of regioselectively deuterated compounds assumed to be precursors of lilac aldehyde and lilac alcohol, respectively. Volatiles were extracted by stir bar sorptive extraction (SBSE) and analyzed using enantioselective multidimensional gas chromatography/mass spectrometry (enantio-MDGC/MS); deuterium-labeled lilac aldehydes and lilac alcohols were separated from unlabeled stereoisomers on a fused silica capillary column, coated with heptakis(2,3-di-O-methyl-6-O-tert-butyldimethylsilyl)-beta-cyclodextrin (DIME-beta-CD) (30%) in SE 52 (70%), as the chiral stationary phase. Feeding experiments with [5,5-(2)H(2)]mevalonic acid lactone 22 and [5,5-(2)H(2)]deoxy-d-xylose 23 indicate that the novel mevalonate independent 1-deoxy-d-xylose 5-phosphate/2C-methyl-d-erythritol 4-phosphate pathway is the dominant metabolic route for biosynthesis in lilac flowers. Additionally, bioconversion of deuterium-labeled d(5)-(R/S)-linalool 3, d(6)-(R)-linalool 21, d(5)-(R/S)-8-hydroxylinalool 6, d(5)-(R/S)-8-oxolinalool 7, d(5)-lilac aldehydes 8-11 and d(5)-lilac alcohols 12-15 into lilac during in vivo feeding experiments was investigated and the metabolic pathway is discussed. Incubation of petals with an aqueous solution of deuterated d(5)-(R/S)-linalool 3 indicates an autonomic terpene biosynthesis of lilac flavor compounds in the flower petals of lilac.

  17. Integration Host Factor (IHF binds to the promoter region of the phtD operon involved in phaseolotoxin synthesis in P. syringae pv. phaseolicola NPS3121

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    Álvarez-Morales Ariel

    2011-05-01

    Full Text Available Abstract Background Pseudomonas syringae pv. phaseolicola, the causal agent of halo blight disease in beans, produces a toxin known as phaseolotoxin, in whose synthesis participate a group of genes organized within the genome in a region known as the "Pht cluster". This region, which is thought to have been acquired by horizontal gene transfer, includes 5 transcriptional units, two monocistronic (argK, phtL and three polycistronic (phtA, phtD, phtM, whose expression is temperature dependent. So far, the regulatory mechanisms involved in phaseolotoxin synthesis have not been elucidated and the only well-established fact is the requirement of low temperatures for its synthesis. In this work, we searched for regulatory proteins that could be involved in phaseolotoxin synthesis, focusing on the regulation of the phtD operon. Results In this study we identified the global regulator IHF (Integration Host Factor, which binds to the promoter region of the phtD operon, exerting a negative effect on the expression of this operon. This is the first regulatory protein identified as part of the phaseolotoxin synthesis system. Our findings suggest that the Pht cluster was similarly regulated in the ancestral cluster by IHF or similar protein, and integrated into the global regulatory mechanism of P. syringae pv. phaseolicola, after the horizontal gene transfer event by using the host IHF protein. Conclusion This study identifies the IHF protein as one element involved in the regulation of phaseolotoxin synthesis in P. syringae pv. phaseolicola NPS3121 and provides new insights into the regulatory mechanisms involved in phaseolotoxin production.

  18. Modeling and mapping the current and future distribution of Pseudomonas syringae pv. actinidiae under climate change in China.

    Science.gov (United States)

    Wang, Rulin; Li, Qing; He, Shisong; Liu, Yuan; Wang, Mingtian; Jiang, Gan

    2018-01-01

    Bacterial canker of kiwifruit caused by Pseudomonas syringae pv. actinidiae (Psa) is a major threat to the kiwifruit industry throughout the world and accounts for substantial economic losses in China. The aim of the present study was to test and explore the possibility of using MaxEnt (maximum entropy models) to predict and analyze the future large-scale distribution of Psa in China. Based on the current environmental factors, three future climate scenarios, which were suggested by the fifth IPCC report, and the current distribution sites of Psa, MaxEnt combined with ArcGIS was applied to predict the potential suitable areas and the changing trend of Psa in China. The jackknife test and correlation analysis were used to choose dominant climatic factors. The receiver operating characteristic curve (ROC) drawn by MaxEnt was used to evaluate the accuracy of the simulation. The results showed that under current climatic conditions, the area from latitude 25° to 36°N and from longitude 101° to 122°E is the primary potential suitable area of Psa in China. The highly suitable area (with suitability between 66 and 100) was mainly concentrated in Northeast Sichuan, South Shaanxi, most of Chongqing, West Hubei and Southwest Gansu and occupied 4.94% of land in China. Under different future emission scenarios, both the areas and the centers of the suitable areas all showed differences compared with the current situation. Four climatic variables, i.e., maximum April temperature (19%), mean temperature of the coldest quarter (14%), precipitation in May (11.5%) and minimum temperature in October (10.8%), had the largest impact on the distribution of Psa. The MaxEnt model is potentially useful for forecasting the future adaptive distribution of Psa under climate change, and it provides important guidance for comprehensive management.

  19. Arabidopsis HARMLESS TO OZONE LAYER protein methylates a glucosinolate breakdown product and functions in resistance to Pseudomonas syringae pv. maculicola.

    Science.gov (United States)

    Nagatoshi, Yukari; Nakamura, Tatsuo

    2009-07-17

    Almost all of the chlorine-containing gas emitted from natural sources is methyl chloride (CH(3)Cl), which contributes to the destruction of the stratospheric ozone layer. Tropical and subtropical plants emit substantial amounts of CH(3)Cl. A gene involved in CH(3)Cl emission from Arabidopsis was previously identified and designated HARMLESS TO OZONE LAYER (hereafter AtHOL1) based on the mutant phenotype. Our previous studies demonstrated that AtHOL1 and its homologs, AtHOL2 and AtHOL3, have S-adenosyl-l-methionine-dependent methyltransferase activities. However, the physiological functions of AtHOLs have yet to be elucidated. In the present study, our comparative kinetic analyses with possible physiological substrates indicated that all of the AtHOLs have low activities toward chloride. AtHOL1 was highly reactive to thiocyanate (NCS(-)), a pseudohalide, synthesizing methylthiocyanate (CH(3)SCN) with a very high k(cat)/K(m) value. We demonstrated in vivo that substantial amounts of NCS(-) were synthesized upon tissue damage in Arabidopsis and that NCS(-) was largely derived from myrosinase-mediated hydrolysis of glucosinolates. Analyses with the T-DNA insertion Arabidopsis mutants (hol1, hol2, and hol3) revealed that only hol1 showed increased sensitivity to NCS(-) in medium and a concomitant lack of CH(3)SCN synthesis upon tissue damage. Bacterial growth assays indicated that the conversion of NCS(-) into CH(3)SCN dramatically increased antibacterial activities against Arabidopsis pathogens that normally invade the wound site. Furthermore, hol1 seedlings showed an increased susceptibility toward an Arabidopsis pathogen, Pseudomonas syringae pv. maculicola. Here we propose that AtHOL1 is involved in glucosinolate metabolism and defense against phytopathogens. Moreover, CH(3)Cl synthesized by AtHOL1 could be considered a byproduct of NCS(-) metabolism.

  20. The levels of nitrite and nitrate, proline and protein profiles in tomato plants infected with pseudomonas syringae

    International Nuclear Information System (INIS)

    Berber, I.; Onlu, H.

    2012-01-01

    In this study, the contents of nitrite-nitrate and free L-proline, and pathogenesis-related (PR) proteins in tomato plants following inoculation with Pseudomonas syringae pv. tomato strain were examined. The results of the nitrite and nitrate indicated that there was a reduction in the levels of nitrate in the infected tomato plants through 1-8 study days, compared with the healthy plants. On the other hands, when the nitrite amounts increased in the first and second days, the nitrite concentrations reduced in infected plants at subsequent time periods, compared with uninfected plants. The accumulation of free proline increased in the infected plants, according to control plants. The whole-cell protein profiles displayed that the levels of the protein bands of molecular masses 204.6 kDa and 69.9 kDa significantly increased in infected and uninfected plants during 2-10 study days. In additionally, in the quantities of the protein bands of molecular weights 90.3 and 79.4 kDa were observed an increase in the infected and healthy plants after the fourth day. However, the protein band of molecular weight 54.3 kDa was visible only in uninfected plants for the fourth and eighth days. Finally, the study suggest that there were the sophisticate relationships among the proline accumulation, the conversion of nitrate to nitrite and the induction of PR protein genes in the regulation of defense mechanisms toward microbial invaders. Our results also indicated that the increases in nitrite and proline contents might be useful indicator for the response toward pathogen attacks. (author)

  1. Allelic variation in two distinct Pseudomonas syringae flagellin epitopes modulates the strength of plant immune responses but not bacterial motility

    Science.gov (United States)

    Clarke, Christopher R.; Chinchilla, Delphine; Hind, Sarah R.; Taguchi, Fumiko; Miki, Ryuji; Ichinose, Yuki; Martin, Gregory B.; Leman, Scotland; Felix, Georg; Vinatzer, Boris A.

    2013-01-01

    Summary The bacterial flagellin (FliC) epitopes flg22 and flgII-28 are microbe-associated molecular patterns (MAMPs). While flg22 is recognized by many plant species via the pattern recognition receptor FLS2, neither the flgII-28 receptor nor the extent of flgII-28 recognition by different plant families is known.Here we tested the significance of flgII-28 as a MAMP and the importance of allelic diversity in flg22 and flgII-28 in plant–pathogen interactions using purified peptides and a Pseudomonas syringae ΔfliC mutant complemented with different fliC alleles.Plant genotype and allelic diversity in flg22 and flgII-28 were found to significantly affect the plant immune response but not bacterial motility. Recognition of flgII-28 is restricted to a number of Solanaceous species. While the flgII-28 peptide does not trigger any immune response in Arabidopsis, mutations in both flg22 and flgII-28 have FLS2-dependent effects on virulence. However, expression of a tomato allele of FLS2 does not confer to Nicotiana benthamiana the ability to detect flgII-28 and tomato plants silenced for FLS2 are not altered in flgII-28 recognition.Therefore, MAMP diversification is an effective pathogen virulence strategy and flgII-28 appears to be perceived by a yet unidentified receptor in the Solanaceae although it has an FLS2-dependent virulence effect in Arabidopsis. PMID:23865782

  2. Molecular characterization and functional analysis of chalcone synthase from Syringa oblata Lindl. in the flavonoid biosynthetic pathway.

    Science.gov (United States)

    Wang, Yu; Dou, Ying; Wang, Rui; Guan, Xuelian; Hu, Zenghui; Zheng, Jian

    2017-11-30

    The flower color of Syringa oblata Lindl., which is often modulated by the flavonoid content, varies and is an important ornamental feature. Chalcone synthase (CHS) catalyzes the first key step in the flavonoid biosynthetic pathway. However, little is known about the role of S. oblata CHS (SoCHS) in flavonoid biosynthesis in this species. Here, we isolate and analyze the cDNA (SoCHS1) that encodes CHS in S. oblata. We also sought to analyzed the molecular characteristics and function of flavonoid metabolism by SoCHS1. We successfully isolated the CHS-encoding genomic DNA (gDNA) in S. oblata (SoCHS1), and the gene structural analysis indicated it had no intron. The opening reading frame (ORF) sequence of SoCHS1 was 1170bp long and encoded a 389-amino acid polypeptide. Multiple sequence alignment revealed that both the conserved CHS active site residues and CHS signature sequence were in the deduced amino acid sequence of SoCHS1. Crystallographic analysis revealed that the protein structure of SoCHS1 is highly similar to that of FnCHS1 in Freesia hybrida. The quantitative real-time polymerase chain reaction (PCR) performed to detect the SoCHS1 transcript expression levels in flowers, and other tissues revealed the expression was significantly correlated with anthocyanin accumulation during flower development. The ectopic expression results of Nicotiana tabacum showed that SoCHS1 overexpression in transgenic tobacco changed the flower color from pale pink to pink. In conclusion, these results suggest that SoCHS1 plays an essential role in flavonoid biosynthesis in S. oblata, and could be used to modify flavonoid components in other plant species. Copyright © 2017. Published by Elsevier B.V.

  3. Protection of Arabidopsis thaliana against leaf-pathogenic Pseudomonas syringae by Sphingomonas strains in a controlled model system.

    Science.gov (United States)

    Innerebner, Gerd; Knief, Claudia; Vorholt, Julia A

    2011-05-01

    Diverse bacterial taxa live in association with plants without causing deleterious effects. Previous analyses of phyllosphere communities revealed the predominance of few bacterial genera on healthy dicotyl plants, provoking the question of whether these commensals play a particular role in plant protection. Here, we tested two of them, Methylobacterium and Sphingomonas, with respect to their ability to diminish disease symptom formation and the proliferation of the foliar plant pathogen Pseudomonas syringae pv. tomato DC3000 on Arabidopsis thaliana. Plants were grown under gnotobiotic conditions in the absence or presence of the potential antagonists and then challenged with the pathogen. No effect of Methylobacterium strains on disease development was observed. However, members of the genus Sphingomonas showed a striking plant-protective effect by suppressing disease symptoms and diminishing pathogen growth. A survey of different Sphingomonas strains revealed that most plant isolates protected A. thaliana plants from developing severe disease symptoms. This was not true for Sphingomonas strains isolated from air, dust, or water, even when they reached cell densities in the phyllosphere comparable to those of the plant isolates. This suggests that plant protection is common among plant-colonizing Sphingomonas spp. but is not a general trait conserved within the genus Sphingomonas. The carbon source profiling of representative isolates revealed differences between protecting and nonprotecting strains, suggesting that substrate competition plays a role in plant protection by Sphingomonas. However, other mechanisms cannot be excluded at this time. In conclusion, the ability to protect plants as shown here in a model system may be an unexplored, common trait of indigenous Sphingomonas spp. and may be of relevance under natural conditions.

  4. Early changes in apoplast composition associated with defence and disease in interactions between Phaseolus vulgaris and the halo blight pathogen Pseudomonas syringae Pv. phaseolicola.

    Science.gov (United States)

    O'Leary, Brendan M; Neale, Helen C; Geilfus, Christoph-Martin; Jackson, Robert W; Arnold, Dawn L; Preston, Gail M

    2016-10-01

    The apoplast is the arena in which endophytic pathogens such as Pseudomonas syringae grow and interact with plant cells. Using metabolomic and ion analysis techniques, this study shows how the composition of Phaseolus vulgaris leaf apoplastic fluid changes during the first six hours of compatible and incompatible interactions with two strains of P. syringae pv. phaseolicola (Pph) that differ in the presence of the genomic island PPHGI-1. Leaf inoculation with the avirulent island-carrying strain Pph 1302A elicited effector-triggered immunity (ETI) and resulted in specific changes in apoplast composition, including increases in conductivity, pH, citrate, γ-aminobutyrate (GABA) and K(+) , that are linked to the onset of plant defence responses. Other apoplastic changes, including increases in Ca(2+) , Fe(2/3+) Mg(2+) , sucrose, β-cyanoalanine and several amino acids, occurred to a relatively similar extent in interactions with both Pph 1302A and the virulent, island-less strain Pph RJ3. Metabolic footprinting experiments established that Pph preferentially metabolizes malate, glucose and glutamate, but excludes certain other abundant apoplastic metabolites, including citrate and GABA, until preferred metabolites are depleted. These results demonstrate that Pph is well-adapted to the leaf apoplast metabolic environment and that loss of PPHGI-1 enables Pph to avoid changes in apoplast composition linked to plant defences. © 2016 The Authors. Plant, Cell & Environment published by John Wiley & Sons Ltd.

  5. NADPH-dependent thioredoxin reductase C plays a role in nonhost disease resistance against Pseudomonas syringae pathogens by regulating chloroplast-generated reactive oxygen species

    Directory of Open Access Journals (Sweden)

    Yasuhiro Ishiga

    2016-04-01

    Full Text Available Chloroplasts are cytoplasmic organelles for photosynthesis in eukaryotic cells. In addition, recent studies have shown that chloroplasts have a critical role in plant innate immunity against invading pathogens. Hydrogen peroxide is a toxic by-product from photosynthesis, which also functions as a signaling compound in plant innate immunity. Therefore, it is important to regulate the level of hydrogen peroxide in response to pathogens. Chloroplasts maintain components of the redox detoxification system including enzymes such as 2-Cys peroxiredoxins (2-Cys Prxs, and NADPH-dependent thioredoxin reductase C (NTRC. However, the significance of 2-Cys Prxs and NTRC in the molecular basis of nonhost disease resistance is largely unknown. We evaluated the roles of Prxs and NTRC using knock-out mutants of Arabidopsis in response to nonhost Pseudomonas syringae pathogens. Plants lacking functional NTRC showed localized cell death (LCD accompanied by the elevated accumulation of hydrogen peroxide in response to nonhost pathogens. Interestingly, the Arabidopsis ntrc mutant showed enhanced bacterial growth and disease susceptibility of nonhost pathogens. Furthermore, the expression profiles of the salicylic acid (SA and jasmonic acid (JA-mediated signaling pathways and phytohormone analyses including SA and JA revealed that the Arabidopsis ntrc mutant shows elevated JA-mediated signaling pathways in response to nonhost pathogen. These results suggest the critical role of NTRC in plant innate immunity against nonhost P. syringae pathogens.

  6. Arabidopsis GH3-LIKE DEFENSE GENE 1 is required for accumulation of salicylic acid, activation of defense responses and resistance to Pseudomonas syringae.

    Science.gov (United States)

    Jagadeeswaran, Guru; Raina, Surabhi; Acharya, Biswa R; Maqbool, Shahina B; Mosher, Stephen L; Appel, Heidi M; Schultz, Jack C; Klessig, Daniel F; Raina, Ramesh

    2007-07-01

    In Arabidopsis, the GH3-like gene family consists of 19 members, several of which have been shown to adenylate the plant hormones jasmonic acid, indole acetic acid and salicylic acid (SA). In some cases, this adenylation has been shown to catalyze hormone conjugation to amino acids. Here we report molecular characterization of the GH3-LIKE DEFENSE GENE 1 (GDG1), a member of the GH3-like gene family, and show that GDG1 is an important component of SA-mediated defense against the bacterial pathogen Pseudomonas syringae. Expression of GDG1 is induced earlier and to a higher level in response to avirulent pathogens compared to virulent pathogens. gdg1 null mutants are compromised in several pathogen defense responses, including activation of defense genes and resistance against virulent and avirulent bacterial pathogens. Accumulation of free and glucoside-conjugated SA (SAG) in response to pathogen infection is compromised in gdg1 mutants. All defense-related phenotypes of gdg1 can be rescued by external application of SA, suggesting that gdg1 mutants are defective in the SA-mediated defense pathway(s) and that GDG1 functions upstream of SA. Our results suggest that GDG1 contributes to both basal and resistance gene-mediated inducible defenses against P. syringae (and possibly other pathogens) by playing a critical role in regulating the levels of pathogen-inducible SA. GDG1 is allelic to the PBS3 (avrPphB susceptible) gene.

  7. Induction of Pseudomonas syringae pv. tomato DC3000 MexAB-OprM multidrug efflux pump by flavonoids is mediated by the repressor PmeR.

    Science.gov (United States)

    Vargas, Paola; Felipe, Antonia; Michán, Carmen; Gallegos, María-Trinidad

    2011-10-01

    In this study, we have analyzed the expression of the Pseudomonas syringae pv. tomato DC3000 mexAB-oprM efflux pump operon and of the regulatory gene pmeR, and we have investigated the role of the PmeR protein on transcription from both promoters. We demonstrate that mexAB-oprM and pmeR are expressed in vivo at a relatively high and moderate basal level, respectively, which, in both cases, increases in the presence of different flavonoids and other compounds, such as butyl and methylparaben. We show that PmeR is the local repressor of the mexAB-oprM promoter and is able to regulate its own expression. The mechanism for this regulation includes binding to a pseudopalindromic operator site which overlaps both mexAB-oprM and pmeR promoters. We have also proven that flavonoids are able to interact with PmeR and induce a conformational change that interferes with the DNA binding ability of PmeR, thereby modulating mexAB-oprM and pmeR expression. Finally, we demonstrate by in vivo experiments that the PmeR/MexAB-OprM system contributes to the colonization of tomato plants. These results provide new insight into a transcriptional regulator and a transport system that play essential roles in the ability of P. syringae pv. tomato DC3000 to resist the action of flavonoids produced by the host.

  8. An insight into the photodynamic approach versus copper formulations in the control of Pseudomonas syringae pv. actinidiae in kiwi plants.

    Science.gov (United States)

    Jesus, Vânia; Martins, Diana; Branco, Tatiana; Valério, Nádia; Neves, Maria G P M S; Faustino, Maria A F; Reis, Luís; Barreal, Esther; Gallego, Pedro P; Almeida, Adelaide

    2018-02-14

    In the last decade, the worldwide production of kiwi fruit has been highly affected by Pseudomonas syringae pv. actinidiae (Psa), a phytopathogenic bacterium; this has led to severe economic losses that are seriously affecting the kiwi fruit trade. The available treatments for this disease are still scarce, with the most common involving frequently spraying the orchards with copper derivatives, in particular cuprous oxide (Cu 2 O). However, these copper formulations should be avoided due to their high toxicity; therefore, it is essential to search for new approaches for controlling Psa. Antimicrobial photodynamic therapy (aPDT) may be an alternative approach to inactivate Psa. aPDT consists in the use of a photosensitizer molecule (PS) that absorbs light and by transference of the excess of energy or electrons to molecular oxygen forms highly reactive oxygen species (ROS) that can affect different molecular targets, thus being very unlikely to lead to the development of microbe resistance. The aim of the present study was to evaluate the effectiveness of aPDT to photoinactivate Psa, using the porphyrin Tetra-Py + -Me and different light intensities. The degree of inactivation of Psa was assessed using the PS at 5.0 μM under low irradiance (4.0 mW cm -2 ). Afterward, ex vivo experiments, using artificially contaminated kiwi leaves, were conducted with a PS at 50 μM under 150 mW cm -2 and sunlight irradiation. A reduction of 6 log in the in vitro assays after 90 min of irradiation was observed. In the ex vivo tests, the decrease was lower, approximately 1.8 log reduction at an irradiance of 150 mW cm -2 , 1.2 log at 4.0 mW cm -2 , and 1.5 log under solar radiation. However, after three successive cycles of treatment under 150 mW cm -2 , a 4 log inactivation was achieved. No negative effects were observed on leaves after treatment. Assays using Cu 2 O were also performed at the recommended concentration by law (50 g h L -1 ) and at concentrations 10 times

  9. Antibacterial Activity of Cinnamaldehyde and Estragole Extracted from Plant Essential Oils against Pseudomonas syringae pv. actinidiae Causing Bacterial Canker Disease in Kiwifruit

    Directory of Open Access Journals (Sweden)

    Yu-Rim Song

    2016-08-01

    Full Text Available Pseudomonas syringae pv. actinidiae (Psa causes bacterial canker disease in kiwifruit. Antibacterial activity of plant essential oils (PEOs originating from 49 plant species were tested against Psa by a vapor diffusion and a liquid culture assays. The five PEOs from Pimenta racemosa, P. dioica, Melaleuca linariifolia, M. cajuputii, and Cinnamomum cassia efficiently inhibited Psa growth by either assays. Among their major components, estragole, eugenol, and methyl eugenol showed significant antibacterial activity by only the liquid culture assay, while cinnamaldehyde exhibited antibacterial activity by both assays. The minimum inhibitory concentrations (MICs of estragole and cinnamaldehyde by the liquid culture assay were 1,250 and 2,500 ppm, respectively. The MIC of cinnamaldehyde by the vapor diffusion assay was 5,000 ppm. Based on the formation of clear zones or the decrease of optical density caused by these compounds, they might kill the bacterial cells and this feature might be useful for managing the bacterial canker disease in kiwifruit.

  10. The observation of mitochondrial movement and ATG5 position in Arabidopsis during the process of infection with virulent and avirulent P. syringae strains

    Science.gov (United States)

    Yang, Liu; Ma, Chao; Chen, Wen li

    2012-03-01

    Infection of plants with pathogens leads to programmed cell death (PCD) associated with the pathogen-triggered hypersensitive response (HR) during plant innate immunity. In this study, the effects of infection by virulent Pseudomonas syringae pv. tomato (Pst) DC3000 and strains harboring avirulence factors AvrRps4 on the induction of HR-PCD were compared. We used Arabidopsis thaliana plants as materials, which expressed green fluorescent protein labeled mitochondria (mito-GFP) and green fluorescent protein tagged ATG5 (ATG5-GFP), these GFP are instantaneous expression. We found both Pst DC3000 and Pst-avrRps4 could induce mitochondria to assemble, the effect of Pst DC3000 was more obvious. ATG5 was located in chloroplasts after infection with Pst DC3000 or Pst-avrRps4. Under the condition of Pst-avrRps4, the expression of ATG5 was stronger than Pst DC3000 treatment.

  11. Biogenetic studies in Syringa vulgaris L.: bioconversion of (18)O(2H)-labeled precursors into lilac aldehydes and lilac alcohols.

    Science.gov (United States)

    Burkhardt, Dirk; Mosandl, Armin

    2003-12-03

    Syringa vulgaris L. inflorescences, petals, and chloroplasts, isolated from lilac flower petals, were fed with aqueous solutions of (18)O-labeled linalool and [5,5-(2)H(2)]-deoxy-d-xylose (DOX). The chloroplasts of lilac flower petals were isolated after feeding experiments with labeled precursors. Volatiles from the chloroplasts were extracted by stir bar sorptive extraction (SBSE) and analyzed using enantioselective multidimensional gas chromatography-mass spectrometry (enantio-MDGC-MS). Feeding experiments with DOX indicate that the novel mevalonate-independent 1-deoxy-d-xylose 5-phosphate/2C-methyl-d-erythritol 4-phosphate (DOX/MEP) is the decisive pathway of lilac aldehyde and lilac alcohol, respectively. Bioconversion of [(18)O]linalool into lilac aldehyde and lilac alcohol during in vivo feeding experiments was monitored, and the metabolic pathways are discussed.

  12. Transgenic expression of antimicrobial peptide D2A21 confers resistance to diseases incited by Pseudomonas syringae pv. tabaci and Xanthomonas citri, but not Candidatus Liberibacter asiaticus.

    Directory of Open Access Journals (Sweden)

    Guixia Hao

    Full Text Available Citrus Huanglongbing (HLB associated with 'Candidatus Liberibacter asiaticus' (Las and citrus canker disease incited by Xanthomonas citri are the most devastating citrus diseases worldwide. To control citrus HLB and canker disease, we previously screened over forty antimicrobial peptides (AMPs in vitro for their potential application in genetic engineering. D2A21 was one of the most active AMPs against X. citri, Agrobacterium tumefaciens and Sinorhizobium meliloti with low hemolysis activity. Therefore, we conducted this work to assess transgenic expression of D2A21 peptide to achieve citrus resistant to canker and HLB. We generated a construct expressing D2A21 and initially transformed tobacco as a model plant. Transgenic tobacco expressing D2A21 was obtained by Agrobacterium-mediated transformation. Successful transformation and D2A21 expression was confirmed by molecular analysis. We evaluated disease development incited by Pseudomonas syringae pv. tabaci in transgenic tobacco. Transgenic tobacco plants expressing D2A21 showed remarkable disease resistance compared to control plants. Therefore, we performed citrus transformations with the same construct and obtained transgenic Carrizo citrange. Gene integration and gene expression in transgenic plants were determined by PCR and RT-qPCR. Transgenic Carrizo expressing D2A21 showed significant canker resistance while the control plants showed clear canker symptoms following both leaf infiltration and spray inoculation with X. citri 3213. Transgenic Carrizo plants were challenged for HLB evaluation by grafting with Las infected rough lemon buds. Las titer was determined by qPCR in the leaves and roots of transgenic and control plants. However, our results showed that transgenic plants expressing D2A21 did not significantly reduce Las titer compared to control plants. We demonstrated that transgenic expression of D2A21 conferred resistance to diseases incited by P. syringae pv. tabaci and X. citri

  13. Functional analysis of endo-1,4-β-glucanases in response to Botrytis cinerea and Pseudomonas syringae reveals their involvement in plant-pathogen interactions.

    Science.gov (United States)

    Finiti, I; Leyva, M O; López-Cruz, J; Calderan Rodrigues, B; Vicedo, B; Angulo, C; Bennett, A B; Grant, M; García-Agustín, P; González-Bosch, C

    2013-09-01

    Plant cell wall modification is a critical component in stress responses. Endo-1,4-β-glucanases (EGs) take part in cell wall editing processes, e.g. elongation, ripening and abscission. Here we studied the infection response of Solanum lycopersicum and Arabidopsis thaliana with impaired EGs. Transgenic TomCel1 and TomCel2 tomato antisense plants challenged with Pseudomonas syringae showed higher susceptibility, callose priming and increased jasmonic acid pathway marker gene expression. These two EGs could be resistance factors and may act as negative regulators of callose deposition, probably by interfering with the defence-signalling network. A study of a set of Arabidopsis EG T-DNA insertion mutants challenged with P. syringae and Botrytis cinerea revealed that the lack of other EGs interferes with infection phenotype, callose deposition, expression of signalling pathway marker genes and hormonal balance. We conclude that a lack of EGs could alter plant response to pathogens by modifying the properties of the cell wall and/or interfering with signalling pathways, contributing to generate the appropriate signalling outcomes. Analysis of microarray data demonstrates that EGs are differentially expressed upon many different plant-pathogen challenges, hormone treatments and many abiotic stresses. We found some Arabidopsis EG mutants with increased tolerance to osmotic and salt stress. Our results show that impairing EGs can alter plant-pathogen interactions and may contribute to appropriate signalling outcomes in many different biotic and abiotic plant stress responses. © 2013 German Botanical Society and The Royal Botanical Society of the Netherlands.

  14. Evolutionary relationship of disease resistance genes in soybean and Arabidopsis specific for the Pseudomonas syringae effectors AvrB and AvrRpm1.

    Science.gov (United States)

    Ashfield, Tom; Redditt, Thomas; Russell, Andrew; Kessens, Ryan; Rodibaugh, Natalie; Galloway, Lauren; Kang, Qing; Podicheti, Ram; Innes, Roger W

    2014-09-01

    In Arabidopsis (Arabidopsis thaliana), the Pseudomonas syringae effector proteins AvrB and AvrRpm1 are both detected by the RESISTANCE TO PSEUDOMONAS MACULICOLA1 (RPM1) disease resistance (R) protein. By contrast, soybean (Glycine max) can distinguish between these effectors, with AvrB and AvrRpm1 being detected by the Resistance to Pseudomonas glycinea 1b (Rpg1b) and Rpg1r R proteins, respectively. We have been using these genes to investigate the evolution of R gene specificity and have previously identified RPM1 and Rpg1b. Here, we report the cloning of Rpg1r, which, like RPM1 and Rpg1b, encodes a coiled-coil (CC)-nucleotide-binding (NB)-leucine-rich repeat (LRR) protein. As previously found for Rpg1b, we determined that Rpg1r is not orthologous with RPM1, indicating that the ability to detect both AvrB and AvrRpm1 evolved independently in soybean and Arabidopsis. The tightly linked soybean Rpg1b and Rpg1r genes share a close evolutionary relationship, with Rpg1b containing a recombination event that combined a NB domain closely related to Rpg1r with CC and LRR domains from a more distantly related CC-NB-LRR gene. Using structural modeling, we mapped polymorphisms between Rpg1b and Rpg1r onto the predicted tertiary structure of Rpg1b, which revealed highly polymorphic surfaces within both the CC and LRR domains. Assessment of chimeras between Rpg1b and Rpg1r using a transient expression system revealed that AvrB versus AvrRpm1 specificity is determined by the C-terminal portion of the LRR domain. The P. syringae effector AvrRpt2, which targets RPM1 INTERACTOR4 (RIN4) proteins in both Arabidopsis and soybean, partially blocked recognition of both AvrB and AvrRpm1 in soybean, suggesting that both Rpg1b and Rpg1r may detect these effectors via modification of a RIN4 homolog. © 2014 American Society of Plant Biologists. All Rights Reserved.

  15. Expression of Vitis amurensis VaERF20 in Arabidopsis thaliana Improves Resistance to Botrytis cinerea and Pseudomonas syringae pv. Tomato DC3000.

    Science.gov (United States)

    Wang, Mengnan; Zhu, Yanxun; Han, Rui; Yin, Wuchen; Guo, Chunlei; Li, Zhi; Wang, Xiping

    2018-03-01

    Ethylene response factor (ERF) transcription factors play important roles in regulating immune responses in plants. In our study, we characterized a member of the ERF transcription factor family, VaERF20 , from the Chinese wild Vitis genotype, V. amurensis Rupr "Shuangyou". Phylogenetic analysis indicated that VaERF20 belongs to group IXc of the ERF family, in which many members are known to contribute to fighting pathogen infection. Consistent with this, expression of VaERF20 was induced by treatment with the necrotrophic fungal pathogen Botrytis cinerea (B. cinerea ) in "Shuangyou" and V. vinifera "Red Globe". Arabidopsis thaliana plants over-expressing VaERF20 displayed enhanced resistance to B. cinerea and the bacterium Pseudomonas syringae pv. tomato ( Pst ) DC3000. Patterns of pathogen-induced reactive oxygen species (ROS) accumulation were entirely distinct in B. cinerea and Pst DC3000 inoculated plants. Examples of both salicylic acid (SA) and jasmonic acid/ethylene (JA/ET) responsive defense genes were up-regulated after B. cinerea and Pst DC3000 inoculation of the VaERF20 -overexpressing transgenic A. thaliana plants. Evidence of pattern-triggered immunity (PTI), callose accumulation and stomatal defense, together with increased expression of PTI genes, was also greater in the transgenic lines. These data indicate that VaERF20 participates in various signal transduction pathways and acts as an inducer of immune responses.

  16. Expression of Vitis amurensis VaERF20 in Arabidopsis thaliana Improves Resistance to Botrytis cinerea and Pseudomonas syringae pv. Tomato DC3000

    Directory of Open Access Journals (Sweden)

    Mengnan Wang

    2018-03-01

    Full Text Available Ethylene response factor (ERF transcription factors play important roles in regulating immune responses in plants. In our study, we characterized a member of the ERF transcription factor family, VaERF20, from the Chinese wild Vitis genotype, V. amurensis Rupr “Shuangyou”. Phylogenetic analysis indicated that VaERF20 belongs to group IXc of the ERF family, in which many members are known to contribute to fighting pathogen infection. Consistent with this, expression of VaERF20 was induced by treatment with the necrotrophic fungal pathogen Botrytis cinerea (B. cinerea in “Shuangyou” and V. vinifera “Red Globe”. Arabidopsis thaliana plants over-expressing VaERF20 displayed enhanced resistance to B. cinerea and the bacterium Pseudomonas syringae pv. tomato (Pst DC3000. Patterns of pathogen-induced reactive oxygen species (ROS accumulation were entirely distinct in B. cinerea and PstDC3000 inoculated plants. Examples of both salicylic acid (SA and jasmonic acid/ethylene (JA/ET responsive defense genes were up-regulated after B. cinerea and PstDC3000 inoculation of the VaERF20-overexpressing transgenic A. thaliana plants. Evidence of pattern-triggered immunity (PTI, callose accumulation and stomatal defense, together with increased expression of PTI genes, was also greater in the transgenic lines. These data indicate that VaERF20 participates in various signal transduction pathways and acts as an inducer of immune responses.

  17. The Arabidopsis Elongator complex is required for nonhost resistance against the bacterial pathogens Xanthomonas citri subsp. citri and Pseudomonas syringae pv. phaseolicola NPS3121.

    Science.gov (United States)

    An, Chuanfu; Wang, Chenggang; Mou, Zhonglin

    2017-05-01

    Although in recent years nonhost resistance has attracted considerable attention for its broad spectrum and durability, the genetic and mechanistic components of nonhost resistance have not been fully understood. We used molecular and histochemical approaches including quantitative PCR, chromatin immunoprecipitation, and 3,3'-diaminobenzidine and aniline blue staining. The evolutionarily conserved histone acetyltransferase complex Elongator was identified as a major component of nonhost resistance against Xanthomonas citri subsp. citri (Xcc) and Pseudomonas syringae pv. phaseolicola (Psp) NPS3121. Mutations in Elongator genes inhibit Xcc-, Psp NPS3121- and/or flg22-induced defense responses including defense gene expression, callose deposition, and reactive oxygen species (ROS) and salicylic acid (SA) accumulation. Mutations in Elongator also attenuate the ROS-SA amplification loop. We show that suppressed ROS and SA accumulation in Elongator mutants is correlated with reduced expression of the Arabidopsis respiratory burst oxidase homologue AtrbohD and the SA biosynthesis gene ISOCHORISMATE SYNTHASE1 (ICS1). Furthermore, we found that the Elongator subunit ELP2 is associated with the chromatin of AtrbohD and ICS1 and is required for maintaining basal histone H3 acetylation levels in these key defense genes. As both AtrbohD and ICS1 contribute to nonhost resistance against Xcc, our results reveal an epigenetic mechanism by which Elongator regulates nonhost resistance in Arabidopsis. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  18. A possible role for acetylated intermediates in diaminopimelate and tabtoxinine-beta-lactam biosynthesis in Pseudomonas syringae pv. tabaci BR2.024.

    Science.gov (United States)

    Liu, L; Shaw, P D

    1997-01-01

    The deduced product of an open reading frame (ORF3) located in the tabtoxinine-beta-lactam (T beta L) biosynthetic region of Pseudomonas syringae pv. tabaci BR2.024 (BR2.024) has significant sequence homology to the dapD products of other bacteria. dapD encodes L-2,3,4,5-tetrahydrodipicolinate succinyl coenzyme A succinyltransferase (THDPA-ST), an enzyme in the diaminopimelate (DAP) and lysine biosynthetic pathway. Complementation studies, in vitro transcription-translation experiments, and enzymatic assays indicated that ORF3 encodes a product with THDPA-ST activity in Escherichia coli dapD mutant beta 274. However, a BR2.024 mutant with an insert in ORF3 was prototrophic, and only basal THDPA-ST activity was detected in extracts of both parent and mutant. This finding suggested that ORF3 was not required for DAP biosynthesis and that it did not encode a product with THDPA-ST activity. The results of enzymatic studies, indicating that BR2.024 uses acetylated intermediates for DAP biosynthesis, are consistent with the hypothesis that BR2.024 does not need THDPA-ST for DAP biosynthesis. The ORF3 mutant produced reduced levels of tabtoxin, indicating that ORF3 may have a role in T beta L biosynthesis. We have named the gene tabB and have proposed a possible function for the gene product. PMID:9294453

  19. Characterization of dapB, a gene required by Pseudomonas syringae pv. tabaci BR2.024 for lysine and tabtoxinine-beta-lactam biosynthesis.

    Science.gov (United States)

    Liu, L; Shaw, P D

    1997-01-01

    The dapB gene, which encodes L-2,3-dihydrodipicolinate reductase, the second enzyme of the lysine branch of the aspartic amino acid family, was cloned and sequenced from a tabtoxin-producing bacterium, Pseudomonas syringae pv. tabaci BR2.024. The deduced amino acid sequence shared 60 to 90% identity to known dapB gene products from gram-negative bacteria and 19 to 21% identity to the dapB products from gram-positive bacteria. The consensus sequence for the NAD(P)H binding site [(V/I)(A/G)(V/I)XGXXGXXG)] and the proposed substrate binding site (HHRHK) were conserved in the polypeptide. A BR2.024 dapB mutant is a diaminopimelate auxotroph and tabtoxin negative. The addition of a mixture of L-,L-, D,D-, and meso-diaminopimelate to defined media restored growth but not tabtoxin production. Cloned DNA fragments containing the parental dapB gene restored the ability to grow in defined media and tabtoxin production to the dapB mutant. These results indicate that the dapB gene is required for both lysine and tabtoxin biosynthesis, thus providing the first genetic evidence that the biosynthesis of tabtoxin proceeds in part along the lysine biosynthetic pathway. These data also suggest that L-2,3,4,5-tetrahydrodipicolinate is a common intermediate for both lysine and tabtoxin biosynthesis. PMID:8990304

  20. The indoleacetic acid-lysine synthetase gene of Pseudomonas syringae subsp. savastanoi induces developmental alterations in transgenic tobacco and potato plants.

    Science.gov (United States)

    Spena, A; Prinsen, E; Fladung, M; Schulze, S C; Van Onckelen, H

    1991-06-01

    The iaaL gene of Pseudomonas syringae subsp. savastanoi encodes an indoleacetic acid-lysine synthetase that conjugates lysine to indoleacetic acid. A chimaeric gene consisting of the iaaL coding region under the control of the 35S RNA promoter from cauliflower mosaic virus (35SiaaL) has been used to test if iaaL gene expression leads to morphological alterations in tobacco and potato. Transgenic tobacco plantlets bearing this construct have been shown to synthesize IAA-[14C]lysine when fed with [14C]lysine. In late stages of development, their leaves show an increased nastic curvature (epinasty) of the petiole and midvein, a finding suggestive of an abnormal auxin metabolism. The alteration is transmitted to progeny as a dominant Mendelian trait cosegregating with the kanamycin resistance marker. Transgenic potato plants harbouring the construct are also characterized by petiole epinasty. Moreover, 35SiaaL transgenic plants have an increased internode length in potato and decreased root growth in both tobacco and potato. An increased content of IAA-conjugates in leaf blade was found to correlate with the epinastic alterations caused by iaaL gene expression in tobacco leaves. These data provide evidence that IAA conjugation is able to modulate hormone action, suggesting that the widespread endogenous auxin-conjugating activities are of physiological importance.

  1. Gaseous 3-pentanol primes plant immunity against a bacterial speck pathogen, Pseudomonas syringae pv. tomato via salicylic acid and jasmonic acid-dependent signaling pathways in Arabidopsis

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    Geun Cheol eSong

    2015-10-01

    Full Text Available 3-Pentanol is an active organic compound produced by plants and is a component of emitted insect sex pheromones. A previous study reported that drench application of 3-pentanol elicited plant immunity against microbial pathogens and an insect pest in crop plants. Here, we evaluated whether 3-pentanol and the derivatives 1-pentanol and 2-pentanol induced plant systemic resistance using the in vitro I-plate system. Exposure of Arabidopsis seedlings to 10 M and 100 nM 3-pentanol evaporate elicited an immune response to Pseudomonas syringae pv. tomato DC3000. We performed quantitative real-time PCR to investigate the 3-pentanol-mediated Arabidopsis immune responses by determining Pathogenesis-Related (PR gene expression levels associated with defense signaling through SA, JA, and ethylene signaling pathways. The results show that exposure to 3-pentanol and subsequent pathogen challenge upregulated PDF1.2 and PR1 expression. Selected Arabidopsis mutants confirmed that the 3-pentanol-mediated immune response involved salicylic acid (SA and jasmonic acid (JA signaling pathways and the NPR1 gene. Taken together, this study indicates that gaseous 3-pentanol triggers induced resistance in Arabidopsis by priming SA and JA signaling pathways. To our knowledge, this is the first report that a volatile compound of an insect sex pheromone triggers plant systemic resistance against a bacterial pathogen.

  2. Suppression of Plant Immune Responses by the Pseudomonas savastanoi pv. savastanoi NCPPB 3335 Type III Effector Tyrosine Phosphatases HopAO1 and HopAO2

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    María Pilar Castañeda-Ojeda

    2017-05-01

    Full Text Available The effector repertoire of the olive pathogen P. savastanoi pv. savastanoi NCPPB 3335 includes two members of the HopAO effector family, one of the most diverse T3E families of the P. syringae complex. The study described here explores the phylogeny of these dissimilar members, HopAO1 and HopAO2, among the complex and reveals their activities as immune defense suppressors. Although HopAO1 is predominantly encoded by phylogroup 3 strains isolated from woody organs of woody hosts, both HopAO1 and HopAO2 are phylogenetically clustered according to the woody/herbaceous nature of their host of isolation, suggesting host specialization of the HopAO family across the P. syringae complex. HopAO1 and HopAO2 translocate into plant cells and show hrpL-dependent expression, which allows their classification as actively deployed type III effectors. Our data also show that HopAO1 and HopAO2 possess phosphatase activity, a hallmark of the members of this family. Both of them exert an inhibitory effect on early plant defense responses, such as ROS production and callose deposition, and are able to suppress ETI responses induced by the effectorless polymutant of P. syringae pv. tomato DC3000 (DC3000D28E in Nicotiana. Moreover, we demonstrate that a ΔhopAO1 mutant of P. savastanoi NCPBB 3335 exhibits a reduced fitness and virulence in olive plants, which supports the relevance of this effector during the interaction of this strain with its host plants. This work contributes to the field with the first report regarding functional analysis of HopAO homologs encoded by P. syringae or P. savastanoi strains isolated from woody hosts.

  3. Suppression of Plant Immune Responses by the Pseudomonas savastanoi pv. savastanoi NCPPB 3335 Type III Effector Tyrosine Phosphatases HopAO1 and HopAO2

    Science.gov (United States)

    Castañeda-Ojeda, María Pilar; Moreno-Pérez, Alba; Ramos, Cayo; López-Solanilla, Emilia

    2017-01-01

    The effector repertoire of the olive pathogen P. savastanoi pv. savastanoi NCPPB 3335 includes two members of the HopAO effector family, one of the most diverse T3E families of the P. syringae complex. The study described here explores the phylogeny of these dissimilar members, HopAO1 and HopAO2, among the complex and reveals their activities as immune defense suppressors. Although HopAO1 is predominantly encoded by phylogroup 3 strains isolated from woody organs of woody hosts, both HopAO1 and HopAO2 are phylogenetically clustered according to the woody/herbaceous nature of their host of isolation, suggesting host specialization of the HopAO family across the P. syringae complex. HopAO1 and HopAO2 translocate into plant cells and show hrpL-dependent expression, which allows their classification as actively deployed type III effectors. Our data also show that HopAO1 and HopAO2 possess phosphatase activity, a hallmark of the members of this family. Both of them exert an inhibitory effect on early plant defense responses, such as ROS production and callose deposition, and are able to suppress ETI responses induced by the effectorless polymutant of P. syringae pv. tomato DC3000 (DC3000D28E) in Nicotiana. Moreover, we demonstrate that a ΔhopAO1 mutant of P. savastanoi NCPBB 3335 exhibits a reduced fitness and virulence in olive plants, which supports the relevance of this effector during the interaction of this strain with its host plants. This work contributes to the field with the first report regarding functional analysis of HopAO homologs encoded by P. syringae or P. savastanoi strains isolated from woody hosts. PMID:28529516

  4. RNA-seq analysis reveals the role of red light in resistance against Pseudomonas syringae pv. tomato DC3000 in tomato plants.

    Science.gov (United States)

    Yang, You-Xin; Wang, Meng-Meng; Yin, Yan-Ling; Onac, Eugen; Zhou, Guo-Fu; Peng, Sheng; Xia, Xiao-Jian; Shi, Kai; Yu, Jing-Quan; Zhou, Yan-Hong

    2015-02-25

    Plants attenuate their responses to a variety of bacterial and fungal pathogens, leading to higher incidences of pathogen infection at night. However, little is known about the molecular mechanism responsible for the light-induced defence response; transcriptome data would likely facilitate the elucidation of this mechanism. In this study, we observed diurnal changes in tomato resistance to Pseudomonas syringae pv. tomato DC3000 (Pto DC3000), with the greatest susceptibility before midnight. Nightly light treatment, particularly red light treatment, significantly enhanced the resistance; this effect was correlated with increased salicylic acid (SA) accumulation and defence-related gene transcription. RNA-seq analysis revealed that red light induced a set of circadian rhythm-related genes involved in the phytochrome and SA-regulated resistance response. The biosynthesis and signalling pathways of multiple plant hormones (auxin, SA, jasmonate, and ethylene) were co-ordinately regulated following Pto DC3000 infection and red light, and the SA pathway was most significantly affected by red light and Pto DC3000 infection. This result indicates that SA-mediated signalling pathways are involved in red light-induced resistance to pathogens. Importantly, silencing of nonexpressor of pathogensis-related genes 1 (NPR1) partially compromised red light-induced resistance against Pto DC3000. Furthermore, sets of genes involved in redox homeostasis (respiratory burst oxidase homologue, RBOH; glutathione S-transferases, GSTs; glycosyltransferase, GTs), calcium (calmodulin, CAM; calmodulin-binding protein, CBP), and defence (polyphenol oxidase, PPO; nudix hydrolase1, NUDX1) as well as transcription factors (WRKY18, WRKY53, WRKY60, WRKY70) and cellulose synthase were differentially induced at the transcriptional level by red light in response to pathogen challenge. Taken together, our results suggest that there is a diurnal change in susceptibility to Pto DC3000 with greatest

  5. Natural variation for responsiveness to flg22, flgII-28, and csp22 and Pseudomonas syringae pv. tomato in heirloom tomatoes.

    Directory of Open Access Journals (Sweden)

    Selvakumar Veluchamy

    Full Text Available Tomato (Solanum lycopersicum L. is susceptible to many diseases including bacterial speck caused by Pseudomonas syringae pv. tomato. Bacterial speck disease is a serious problem worldwide in tomato production areas where moist conditions and cool temperatures occur. To enhance breeding of speck resistant fresh-market tomato cultivars we identified a race 0 field isolate, NC-C3, of P. s. pv. tomato in North Carolina and used it to screen a collection of heirloom tomato lines for speck resistance in the field. We observed statistically significant variation among the heirloom tomatoes for their response to P. s. pv. tomato NC-C3 with two lines showing resistance approaching a cultivar that expresses the Pto resistance gene, although none of the heirloom lines have Pto. Using an assay that measures microbe-associated molecular pattern (MAMP-induced production of reactive oxygen species (ROS, we investigated whether the heirloom lines showed differential responsiveness to three bacterial-derived peptide MAMPs: flg22 and flgII-28 (from flagellin and csp22 (from cold shock protein. Significant differences were observed for MAMP responsiveness among the lines, although these differences did not correlate strongly with resistance or susceptibility to bacterial speck disease. The identification of natural variation for MAMP responsiveness opens up the possibility of using a genetic approach to identify the underlying loci and to facilitate breeding of cultivars with enhanced disease resistance. Towards this goal, we discovered that responsiveness to csp22 segregates as a single locus in an F2 population of tomato.

  6. Co-silencing of tomato S-adenosylhomocysteine hydrolase genes confers increased immunity against Pseudomonas syringae pv. tomato DC3000 and enhanced tolerance to drought stress

    Directory of Open Access Journals (Sweden)

    Li Xiao Hui

    2015-09-01

    Full Text Available S-adenosylhomocysteine hydrolase (SAHH, catalyzing the reversible hydrolysis of S-adenosylhomocysteine to adenosine and homocysteine, is a key enzyme that maintain the cellular methylation potential in all organisms. We report here the biological functions of tomato SlSAHHs in stress response. The tomato genome contains three SlSAHH genes that encode SlSAHH proteins with high level of sequence identity. qRT-PCR analysis revealed that SlSAHHs responded with distinct expression induction patterns to Pseudomonas syringae pv. tomato (Pst DC3000 and Botrytis cinerea as well as to defense signaling hormones such as salicylic acid, jasmonic acid and a precursor of ethylene. Virus-induced gene silencing-based knockdown of individual SlSAHH gene did not affect the growth performance and the response to Pst DC3000. However, co-silencing of three SlSAHH genes using a conserved sequence led to significant inhibition of vegetable growth. The SlSAHH-co-silenced plants displayed increased resistance to Pst DC3000 but did not alter the resistance to B. cinerea. Co-silencing of SlSAHHs resulted in constitutively activated defense responses including elevated SA level, upregulated expression of defense-related and PAMP-triggered immunity marker genes and increased callose deposition and H2O2 accumulation. Furthermore, the SlSAHH-co-silenced plants also exhibited enhanced drought stress tolerance although they had relatively small roots. These data demonstrate that, in addition to the functions in growth and development, SAHHs also play important roles in regulating biotic and abiotic stress responses in plants.

  7. Tomato Sl3-MMP, a member of the Matrix metalloproteinase family, is required for disease resistance against Botrytis cinerea and Pseudomonas syringae pv. tomato DC3000.

    Science.gov (United States)

    Li, Dayong; Zhang, Huijuan; Song, Qiuming; Wang, Lu; Liu, Shixia; Hong, Yongbo; Huang, Lei; Song, Fengming

    2015-06-14

    Matrix metalloproteinases (MMPs) are a family of zinc-dependent endopeptidases. MMPs have been characterized in detail in mammals and shown to play key roles in many physiological and pathological processes. Although MMPs in some plant species have been identified, the function of MMPs in biotic stress responses remains elusive. A total of five MMP genes were identified in tomato genome. qRT-PCR analysis revealed that expression of Sl-MMP genes was induced with distinct patterns by infection of Botrytis cinerea and Pseudomonas syringae pv. tomato (Pst) DC3000 and by treatment with defense-related hormones such as salicylic acid, jasmonic acid and ethylene precursor 1-amino cyclopropane-1-carboxylic acid. Virus-induced gene silencing (VIGS)-based knockdown of individual Sl-MMPs and disease assays indicated that silencing of Sl3-MMP resulted in reduced resistance to B. cinerea and Pst DC3000, whereas silencing of other four Sl-MMPs did not affect the disease resistance against these two pathogens. The Sl3-MMP-silenced tomato plants responded with increased accumulation of reactive oxygen species and alerted expression of defense genes after infection of B. cinerea. Transient expression of Sl3-MMP in leaves of Nicotiana benthamiana led to an enhanced resistance to B. cinerea and upregulated expression of defense-related genes. Biochemical assays revealed that the recombinant mature Sl3-MMP protein had proteolytic activities in vitro with distinct preferences for specificity of cleavage sites. The Sl3-MMP protein was targeted onto the plasma membrane of plant cells when transiently expressed in onion epidermal cells. VIGS-based knockdown of Sl3-MMP expression in tomato and gain-of-function transient expression of Sl3-MMP in N. benthamiana demonstrate that Sl3-MMP functions as a positive regulator of defense response against B. cinerea and Pst DC3000.

  8. Analysis of volatile compounds emitted from fresh Syringa oblata flowers in different florescence by headspace solid-phase microextraction-gas chromatography-mass spectrometry.

    Science.gov (United States)

    Li, Zu-Guang; Lee, Maw-Rong; Shen, De-Long

    2006-08-18

    In this study, a simple and solvent-free method was developed for determination of the volatile compounds from fresh flowers of Syringa oblata using headspace solid-phase microextraction and gas chromatography-mass spectrometry. The SPME parameters were studied, the optimum conditions of a 65mum polydimethylsiloxan/divinylbenezene (PDMS/DVB), extraction temperature of 25 degrees C and extraction time of 30 min were obtained and applied to extraction of the volatile compounds emitted from fresh flowers of S. oblata. The volatile compounds released from fresh flowers of S. oblata were separated and identified by GC-MS. Lilac aldehyde A, lilac aldehyde B, lilac aldehyde C, lilac aldehyde D, lilac alcohol A, lilac alcohol B, lilac alcohol C, lilac alcohol D, alpha-pinene, sabinene, beta-pinene, myrcene, d-limonene, eucalyptol, cis-ocimene, benzaldehyde, terpinolene, linalool, benzene acetaldehyde, alpha-terpineol, p-methoxyanisole, p-anisaldehyde, (Z,E)-alpha-farnesene and (E,E)-alpha-farnesene were the most abundant volatiles released from fresh flowers of S. oblata var. alba. The relative contents of main volatile fragrance were found to be different in emissions from two varieties of S. oblata flowers (white or purple in color). The four isomers of lilac alcohol and four isomer lilac aldehyde were the characteristic components of the scent of fresh flowers of S. oblata. The main volatile fragrance from fresh flowers of S. oblata var. alba in different florescence ((A) flower buds; (B) at the early stage of flower blooming; (C) during the flower blooming; (D) at the end of flower blooming; (E) senescence) were studied in this paper. The results demonstrated that headspace SPME-GC-MS is a simple, rapid and solvent-free method suitable for analysis of volatile compounds emitted from fresh flowers of S. oblata in different florescence.

  9. Identification of Novel Type III Effectors Using Latent Dirichlet Allocation

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    Yang Yang

    2012-01-01

    Full Text Available Among the six secretion systems identified in Gram-negative bacteria, the type III secretion system (T3SS plays important roles in the disease development of pathogens. T3SS has attracted a great deal of research interests. However, the secretion mechanism has not been fully understood yet. Especially, the identification of effectors (secreted proteins is an important and challenging task. This paper adopts machine learning methods to identify type III secreted effectors (T3SEs. We extract features from amino acid sequences and conduct feature reduction based on latent semantic information by using latent Dirichlet allocation model. The experimental results on Pseudomonas syringae data set demonstrate the good performance of the new methods.

  10. Accurate prediction of secreted substrates and identification of a conserved putative secretion signal for type III secretion systems

    Energy Technology Data Exchange (ETDEWEB)

    Samudrala, Ram; Heffron, Fred; McDermott, Jason E.

    2009-04-24

    The type III secretion system is an essential component for virulence in many Gram-negative bacteria. Though components of the secretion system apparatus are conserved, its substrates, effector proteins, are not. We have used a machine learning approach to identify new secreted effectors. The method integrates evolutionary measures, such as the pattern of homologs in a range of other organisms, and sequence-based features, such as G+C content, amino acid composition and the N-terminal 30 residues of the protein sequence. The method was trained on known effectors from Salmonella typhimurium and validated on a corresponding set of effectors from Pseudomonas syringae, after eliminating effectors with detectable sequence similarity. The method was able to identify all of the known effectors in P. syringae with a specificity of 84% and sensitivity of 82%. The reciprocal validation, training on P. syringae and validating on S. typhimurium, gave similar results with a specificity of 86% when the sensitivity level was 87%. These results show that type III effectors in disparate organisms share common features. We found that maximal performance is attained by including an N-terminal sequence of only 30 residues, which agrees with previous studies indicating that this region contains the secretion signal. We then used the method to define the most important residues in this putative secretion signal. Finally, we present novel predictions of secreted effectors in S. typhimurium, some of which have been experimentally validated, and apply the method to predict secreted effectors in the genetically intractable human pathogen Chlamydia trachomatis. This approach is a novel and effective way to identify secreted effectors in a broad range of pathogenic bacteria for further experimental characterization and provides insight into the nature of the type III secretion signal.

  11. A bacterial type III secretion assay for delivery of fungal effector proteins into wheat.

    Science.gov (United States)

    Upadhyaya, Narayana M; Mago, Rohit; Staskawicz, Brian J; Ayliffe, Michael A; Ellis, Jeffrey G; Dodds, Peter N

    2014-03-01

    Large numbers of candidate effectors from fungal pathogens are being identified through whole-genome sequencing and in planta expression studies. Although Agrobacterium-mediated transient expression has enabled high-throughput functional analysis of effectors in dicot plants, this assay is not effective in cereal leaves. Here, we show that a nonpathogenic Pseudomonas fluorescens engineered to express the type III secretion system (T3SS) of P. syringae and the wheat pathogen Xanthomonas translucens can deliver fusion proteins containing T3SS signals from P. syringae (AvrRpm1) and X. campestris (AvrBs2) avirulence (Avr) proteins, respectively, into wheat leaf cells. A calmodulin-dependent adenylate cyclase reporter protein was delivered effectively into wheat and barley by both bacteria. Absence of any disease symptoms with P. fluorescens makes it more suitable than X. translucens for detecting a hypersensitive response (HR) induced by an effector protein with avirulence activity. We further modified the delivery system by removal of the myristoylation site from the AvrRpm1 fusion to prevent its localization to the plasma membrane which could inhibit recognition of an Avr protein. Delivery of the flax rust AvrM protein by the modified delivery system into transgenic tobacco leaves expressing the corresponding M resistance protein induced a strong HR, indicating that the system is capable of delivering a functional rust Avr protein. In a preliminary screen of effectors from the stem rust fungus Puccinia graminis f. sp. tritici, we identified one effector that induced a host genotype-specific HR in wheat. Thus, the modified AvrRpm1:effector-Pseudomonas fluorescens system is an effective tool for large-scale screening of pathogen effectors for recognition in wheat.

  12. An untargeted global metabolomic analysis reveals the biochemical changes underlying basal resistance and priming in Solanum lycopersicum, and identifies 1-methyltryptophan as a metabolite involved in plant responses to Botrytis cinerea and Pseudomonas syringae.

    Science.gov (United States)

    Camañes, Gemma; Scalschi, Loredana; Vicedo, Begonya; González-Bosch, Carmen; García-Agustín, Pilar

    2015-10-01

    In this study, we have used untargeted global metabolomic analysis to determine and compare the chemical nature of the metabolites altered during the infection of tomato plants (cv. Ailsa Craig) with Botrytis cinerea (Bot) or Pseudomonas syringae pv. tomato DC3000 (Pst), pathogens that have different invasion mechanisms and lifestyles. We also obtained the metabolome of tomato plants primed using the natural resistance inducer hexanoic acid and then infected with these pathogens. By contrasting the metabolomic profiles of infected, primed, and primed + infected plants, we determined not only the processes or components related directly to plant defense responses, but also inferred the metabolic mechanisms by which pathogen resistance is primed. The data show that basal resistance and hexanoic acid-induced resistance to Bot and Pst are associated with a marked metabolic reprogramming. This includes significant changes in amino acids, sugars and free fatty acids, and in primary and secondary metabolism. Comparison of the metabolic profiles of the infections indicated clear differences, reflecting the fact that the plant's chemical responses are highly adapted to specific attackers. The data also indicate involvement of signaling molecules, including pipecolic and azelaic acids, in response to Pst and, interestingly, to Bot. The compound 1-methyltryptophan was shown to be associated with the tomato-Pst and tomato-Bot interactions as well as with hexanoic acid-induced resistance. Root application of this Trp-derived metabolite also demonstrated its ability to protect tomato plants against both pathogens. © 2015 The Authors The Plant Journal © 2015 John Wiley & Sons Ltd.

  13. Blood Types

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    ... Drive Home Types of Blood Donations Blood Types Blood Types Not all blood is alike. There are eight ... African descent. Learn More About Blood and Diversity Blood Types and Transfusion There are very specific ways in ...

  14. Virus-Induced Gene Silencing-Based Functional Analyses Revealed the Involvement of Several Putative Trehalose-6-Phosphate Synthase/Phosphatase Genes in Disease Resistance against Botrytis cinerea and Pseudomonas syringae pv. tomato DC3000 in Tomato.

    Science.gov (United States)

    Zhang, Huijuan; Hong, Yongbo; Huang, Lei; Liu, Shixia; Tian, Limei; Dai, Yi; Cao, Zhongye; Huang, Lihong; Li, Dayong; Song, Fengming

    2016-01-01

    Trehalose and its metabolism have been demonstrated to play important roles in control of plant growth, development, and stress responses. However, direct genetic evidence supporting the functions of trehalose and its metabolism in defense response against pathogens is lacking. In the present study, genome-wide characterization of putative trehalose-related genes identified 11 SlTPSs for trehalose-6-phosphate synthase, 8 SlTPPs for trehalose-6-phosphate phosphatase and one SlTRE1 for trehalase in tomato genome. Nine SlTPSs, 4 SlTPPs, and SlTRE1 were selected for functional analyses to explore their involvement in tomato disease resistance. Some selected SlTPSs, SlTPPs, and SlTRE1 responded with distinct expression induction patterns to Botrytis cinerea and Pseudomonas syringae pv. tomato (Pst) DC3000 as well as to defense signaling hormones (e.g., salicylic acid, jasmonic acid, and a precursor of ethylene). Virus-induced gene silencing-mediated silencing of SlTPS3, SlTPS4, or SlTPS7 led to deregulation of ROS accumulation and attenuated the expression of defense-related genes upon pathogen infection and thus deteriorated the resistance against B. cinerea or Pst DC3000. By contrast, silencing of SlTPS5 or SlTPP2 led to an increased expression of the defense-related genes upon pathogen infection and conferred an increased resistance against Pst DC3000. Silencing of SlTPS3, SlTPS4, SlTPS5, SlTPS7, or SlTPP2 affected trehalose level in tomato plants with or without infection of B. cinerea or Pst DC3000. These results demonstrate that SlTPS3, SlTPS4, SlTPS5, SlTPS7, and SlTPP2 play roles in resistance against B. cinerea and Pst DC3000, implying the importance of trehalose and tis metabolism in regulation of defense response against pathogens in tomato.

  15. Virus-induced Gene Silencing-based Functional Analyses Revealed the Involvement of Several Putative Trehalose-6-Phosphate Synthase/Phosphatase Genes in Disease Resistance against Botrytis cinerea and Pseudomonas syringae pv. tomato DC3000 in Tomato

    Directory of Open Access Journals (Sweden)

    Huijuan Zhang

    2016-08-01

    Full Text Available Trehalose and its metabolism have been demonstrated to play important roles in control of plant growth, development and stress responses. However, direct genetic evidence supporting the functions of trehalose and its metabolism in defense response against pathogens is lacking. In the present study, genome-wide characterization of putative trehalose-related genes identified 11 SlTPSs for trehalose-6-phosphate synthase, 8 SlTPPs for trehalose-6-phosphate phosphatase and one SlTRE1 for trehalase in tomato genome. Nine SlTPSs, 4 SlTPPs and SlTRE1 were selected for functional analyses to explore their involvement in tomato disease resistance. Some selected SlTPSs, SlTPPs and SlTRE1 responded with distinct expression induction patterns to Botrytis cinerea and Pseudomonas syringae pv. tomato (Pst DC3000 as well as to defense signaling hormones (e.g. salicylic acid, jasmonic acid and a precursor of ethylene. Virus-induced gene silencing-mediated silencing of SlTPS3, SlTPS4 or SlTPS7 led to deregulation of ROS accumulation and attenuated the expression of defense-related genes upon pathogen infection and thus deteriorated the resistance against B. cinerea or Pst DC3000. By contrast, silencing of SlTPS5 or SlTPP2 led to an increased expression of the defense-related genes upon pathogen infection and conferred an increased resistance against Pst DC3000. Silencing of SlTPS3, SlTPS4, SlTPS5, SlTPS7 or SlTPP2 affected trehalose level in tomato plants with or without infection of B. cinerea or Pst DC3000. These results demonstrate that SlTPS3, SlTPS4, SlTPS5, SlTPS7 and SlTPP2 play roles in resistance against B. cinerea and Pst DC3000, implying the importance of trehalose and tis metabolism in regulation of defense response against pathogens in tomato.

  16. Differential modulation of plant immune responses by diverse members of the Pseudomonas savastanoi pv. savastanoi HopAF type III effector family.

    Science.gov (United States)

    Castañeda-Ojeda, M Pilar; López-Solanilla, Emilia; Ramos, Cayo

    2017-06-01

    The Pseudomonas savastanoi pv. savastanoi NCPPB 3335 type III secretion system (T3SS) effector repertoire includes 33 candidates, seven of which translocate into host cells and interfere with plant defences. The present study was performed to investigate the co-existence of both plasmid- and chromosomal-encoded members of the HopAF effector family, HopAF1-1 and HopAF1-2, respectively, in the genome of NCPPB 3335. Here, we show that the HopAF1 paralogues are widely distributed in the Pseudomonas syringae complex, where HopAF1-1 is most similar to the homologues encoded by other P. syringae pathovars infecting woody hosts that belong to phylogroups 1 and 3. We show that the expression of both HopAF1-1 and HopAF-2 is transcriptionally dependent on HrpL and demonstrate their delivery into Nicotiana tabacum leaves. Although the heterologous delivery of either HopAF1-1 or HopAF1-2 significantly suppressed the production of defence-associated reactive oxygen species levels, only HopAF1-2 reduced the levels of callose deposition. Moreover, the expression of HopAF1-2 by functionally effectorless P. syringae pv. tomato DC3000D28E completely inhibited the hypersensitive response in tobacco and significantly increased the competitiveness of the strain in Nicotiana benthamiana. Despite their functional differences, subcellular localization studies reveal that green fluorescent protein (GFP) fusions to either HopAF1-1 or HopAF1-2 are targeted to the plasma membrane when they are expressed in plant cells, a process that is completely dependent on the integrity of their N-myristoylation motif. Our results further support the notion that highly similar T3SS effectors might differentially interact with diverse plant targets, even when they co-localize in the same cell compartment. © 2016 BSPP AND JOHN WILEY & SONS LTD.

  17. WtsE, an AvrE-family type III effector protein of Pantoea stewartii subsp. stewartii, causes cell death in non-host plants.

    Science.gov (United States)

    Ham, Jong Hyun; Majerczak, Doris; Ewert, Sophie; Sreerekha, Mysore-Venkatarau; Mackey, David; Coplin, David

    2008-09-01

    Pantoea stewartii subsp. stewartii (Pnss) causes Stewart's bacterial wilt of sweet corn and leaf blight of maize. The pathogenicity of Pnss depends on synthesis of extracellular polysaccharide and an Hrp type III secretion system. WtsE, a type III secreted effector protein, is essential for the virulence of Pnss on corn. It belongs to the AvrE family of effectors, which includes DspA/E from Erwinia amylovora and AvrE1 from Pseudomonas syringae. Previously, WtsE was shown to cause disease-associated cell death in its host plant, sweet corn. Here, we examine the biological activity of WtsE in several non-host plants. WtsE induced cell death in Nicotiana benthamiana, tobacco, beet and Arabidopsis thaliana when it was transiently produced in plant cells following agroinfiltration or translocated into plant cells from Pnss, Escherichia coli or Pseudomonas syringae pv. phaseolicola (Pph). WtsE-induced cell death in N. benthamiana, tobacco and beet resembled a hypersensitive response and in N. benthamiana it was delayed by cycloheximide. Interestingly, WtsE strongly promoted the growth of Pnss in N. benthamiana prior to the onset of cell death. Deletion derivatives of WtsE that failed to induce cell death in N. benthamiana and tobacco also did not complement wtsE mutants of Pnss for virulence in sweet corn, indicating a correlation between the two activities. WtsE also induced cell death in A. thaliana, where it suppressed basal defences induced by Pph. Thus, WtsE has growth-promoting, defence-suppressing and cell death-inducing activities in non-host plants. Expression of WtsE also prevented the growth of yeast, possibly due to an innate toxicity to eukaryotic cells.

  18. Probing Pseudomonas syringae host interactions using metatranscriptomics

    Science.gov (United States)

    Transcriptome analyses during the interaction of plants and pathogens can be used to provide insights into molecular mechanisms of plant resistance as well as the mechanisms used by bacteria to adapt to hosts and cause disease. We performed a dual in planta RNA-Seq experiment to profile RNA expressi...

  19. Blood typing

    Science.gov (United States)

    Blood typing is a method to tell what type of blood you have. Blood typing is done so you can safely donate your blood or receive a blood transfusion. It is also done to see if you have a substance called Rh factor on the surface of your red ...

  20. Blood Types

    Science.gov (United States)

    ... KidsHealth / For Teens / Blood Types What's in this article? Four Blood Groups... Plus Rh Factor... ...Make Eight Blood Types Why Blood Type Matters Print en español Tipos de sangre About 5 million Americans need blood transfusions every ...

  1. Klebsiella Typing

    DEFF Research Database (Denmark)

    Hansen, D S; Skov, R; Benedí, J.V.

    2002-01-01

    unit (NICU) were K-typed by countercurrent immunoelectrophoresis (CCIE), O-typed by an inhibition enzyme-linked immunosorbent assay method, and typed by pulsed-field gel electrophoresis (PFGE) using the restriction enzyme XbaI. RESULTS: Typing data for the 104 bacteremia isolates were compared......OBJECTIVE: To compare pulsed-field gel electrophoresis (PFGE) typing and O:K-serotyping of Klebsiella in two different epidemiological settings. METHODS: One hundred and four bacteremia isolates without known epidemiological relation and 47 isolates from an outbreak in a neonatal intensive care...

  2. Type Tricks

    DEFF Research Database (Denmark)

    Beier, Sofie

    2017-01-01

    an expert as a typography professor, Sofie Beier knows exactly what the students need to know and how they can improve their skills. ‘Type Tricks’ is not only perfect for students, it also comes in handy for every type designer. It gives them the opportunity to reread information they were thaught at during...

  3. Type inference for correspondence types

    DEFF Research Database (Denmark)

    Hüttel, Hans; Gordon, Andy; Hansen, Rene Rydhof

    2009-01-01

    We present a correspondence type/effect system for authenticity in a π-calculus with polarized channels, dependent pair types and effect terms and show how one may, given a process P and an a priori type environment E, generate constraints that are formulae in the Alternating Least Fixed......-Point (ALFP) logic. We then show how a reasonable model of the generated constraints yields a type/effect assignment such that P becomes well-typed with respect to E if and only if this is possible. The formulae generated satisfy a finite model property; a system of constraints is satisfiable if and only...... if it has a finite model. As a consequence, we obtain the result that type/effect inference in our system is polynomial-time decidable....

  4. Cavity types

    CERN Document Server

    Gerigk, Frank

    2011-01-01

    In the field of particle accelerators the most common use of RF cavities is to increase the particle velocity of traversing particles. This feature makes them one of the core ingredients of every accelerator, and in the case of linear accelerators they are even the dominant machine component. Since there are many different types of accelerator, RF cavities have been optimized for different purposes and with different abilities, e.g., cavities with fixed or variable RF frequency, cavities for short or long pulses/CW operation, superconducting and normal-conducting cavities. This lecture starts with a brief historical introduction and an explanation on how to get from Maxwell's equations to a simple cavity. Then, cavities will be classified by the type of mode that is employed for acceleration, and an explanation is given as to why certain modes are used in particular cavity types. The lecture will close with a comparison of normal versus superconducting cavities and a few words on the actual power consumption ...

  5. Four genes essential for recombination define GInts, a new type of mobile genomic island widespread in bacteria.

    Science.gov (United States)

    Bardaji, Leire; Echeverría, Myriam; Rodríguez-Palenzuela, Pablo; Martínez-García, Pedro M; Murillo, Jesús

    2017-04-10

    Integrases are a family of tyrosine recombinases that are highly abundant in bacterial genomes, actively disseminating adaptive characters such as pathogenicity determinants and antibiotics resistance. Using comparative genomics and functional assays, we identified a novel type of mobile genetic element, the GInt, in many diverse bacterial groups but not in archaea. Integrated as genomic islands, GInts show a tripartite structure consisting of the ginABCD operon, a cargo DNA region from 2.5 to at least 70 kb, and a short AT-rich 3' end. The gin operon is characteristic of GInts and codes for three putative integrases and a small putative helix-loop-helix protein, all of which are essential for integration and excision of the element. Genes in the cargo DNA are acquired mostly from phylogenetically related bacteria and often code for traits that might increase fitness, such as resistance to antimicrobials or virulence. GInts also tend to capture clusters of genes involved in complex processes, such as the biosynthesis of phaseolotoxin by Pseudomonas syringae. GInts integrate site-specifically, generating two flanking direct imperfect repeats, and excise forming circular molecules. The excision process generates sequence variants at the element attachment site, which can increase frequency of integration and drive target specificity.

  6. Facts about Type 2

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    Full Text Available ... In Honor Become a Member En Español Type 1 Type 2 About Us Online Community Meal Planning ... Basics Home Symptoms Diagnosis America's Diabetes Challenge Type 1 Type 2 Facts About Type 2 Enroll in ...

  7. Guarded Dependent Type Theory with Coinductive Types

    DEFF Research Database (Denmark)

    Bizjak, Ales; Grathwohl, Hans Bugge; Clouston, Ranald

    2016-01-01

    , type based, way. Clock quantifiers are used for controlled elimination of the later modality and for encoding coinductive types using guarded recursive types. Key to the development of gDTT are novel type and term formers involving what we call ‘delayed substitutions’. These generalise the applicative...

  8. Accurate prediction of secreted substrates and identification of a conserved putative secretion signal for type III secretion systems.

    Directory of Open Access Journals (Sweden)

    Ram Samudrala

    2009-04-01

    Full Text Available The type III secretion system is an essential component for virulence in many Gram-negative bacteria. Though components of the secretion system apparatus are conserved, its substrates--effector proteins--are not. We have used a novel computational approach to confidently identify new secreted effectors by integrating protein sequence-based features, including evolutionary measures such as the pattern of homologs in a range of other organisms, G+C content, amino acid composition, and the N-terminal 30 residues of the protein sequence. The method was trained on known effectors from the plant pathogen Pseudomonas syringae and validated on a set of effectors from the animal pathogen Salmonella enterica serovar Typhimurium (S. Typhimurium after eliminating effectors with detectable sequence similarity. We show that this approach can predict known secreted effectors with high specificity and sensitivity. Furthermore, by considering a large set of effectors from multiple organisms, we computationally identify a common putative secretion signal in the N-terminal 20 residues of secreted effectors. This signal can be used to discriminate 46 out of 68 total known effectors from both organisms, suggesting that it is a real, shared signal applicable to many type III secreted effectors. We use the method to make novel predictions of secreted effectors in S. Typhimurium, some of which have been experimentally validated. We also apply the method to predict secreted effectors in the genetically intractable human pathogen Chlamydia trachomatis, identifying the majority of known secreted proteins in addition to providing a number of novel predictions. This approach provides a new way to identify secreted effectors in a broad range of pathogenic bacteria for further experimental characterization and provides insight into the nature of the type III secretion signal.

  9. Mucopolysaccharidosis type IV

    Science.gov (United States)

    MPS IV; Morquio syndrome; Mucopolysaccharidosis type IVA; MPS IVA; Galactosamine-6-sulfatase deficiency; Mucopolysaccharidosis type IVB; MPS IVB; Beta galactosidase deficiency; Lysosomal storage disease - mucopolysaccharidosis type IV

  10. Facts about Type 2

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    Full Text Available ... Day Diabetes Basics Home Symptoms Diagnosis America's Diabetes Challenge Type 1 Type 2 Facts About Type 2 ... as well as the aged population. Patient Education Materials — Taking Care of Type 2 Diabetes This two- ...

  11. Facts about Type 2

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    Full Text Available ... Alert Day Diabetes Basics Home Symptoms Diagnosis America's Diabetes Challenge Type 1 Type 2 Facts About Type 2 Enroll in ... Do I Begin With Type2? Living With Type 1 Diabetes Enroll in the Living WIth Type 2 Diabetes ...

  12. Facts about Type 2

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    Full Text Available ... Alert Day Diabetes Basics Home Symptoms Diagnosis America's Diabetes Challenge Type 1 Type 2 Facts About Type 2 Enroll in ... Where Do I Begin With Type2? Living With Type 1 Diabetes Enroll in the Living WIth Type 2 Diabetes ...

  13. The Xanthomonas campestris pv. vesicatoria Type-3 Effector XopB Inhibits Plant Defence Responses by Interfering with ROS Production.

    Directory of Open Access Journals (Sweden)

    Johannes Peter Roman Priller

    Full Text Available The bacterial pathogen Xanthomonas campestris pv. vesicatoria 85-10 (Xcv translocates about 30 type-3 effector proteins (T3Es into pepper plants (Capsicum annuum to suppress plant immune responses. Among them is XopB which interferes with PTI, ETI and sugar-mediated defence responses, but the underlying molecular mechanisms and direct targets are unknown so far. Here, we examined the XopB-mediated suppression of plant defence responses in more detail. Infection of susceptible pepper plants with Xcv lacking xopB resulted in delayed symptom development compared to Xcv wild type infection concomitant with an increased formation of salicylic acid (SA and expression of pathogenesis-related (PR genes. Expression of xopB in Arabidopsis thaliana promoted the growth of the virulent Pseudomonas syringae pv. tomato (Pst DC3000 strain. This was paralleled by a decreased SA-pool and a lower induction of SA-dependent PR gene expression. The expression pattern of early flg22-responsive marker genes indicated that MAPK signalling was not altered in the presence of XopB. However, XopB inhibited the flg22-triggered burst of reactive oxygen species (ROS. Consequently, the transcript accumulation of AtOXI1, a ROS-dependent marker gene, was reduced in xopB-expressing Arabidopsis plants as well as callose deposition. The lower ROS production correlated with a low level of basal and flg22-triggered expression of apoplastic peroxidases and the NADPH oxidase RBOHD. Conversely, deletion of xopB in Xcv caused a higher production of ROS in leaves of susceptible pepper plants. Together our results demonstrate that XopB modulates ROS responses and might thereby compromise plant defence.

  14. Facts about Type 2

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    Full Text Available ... Where Do I Begin With Type2? Living With Type 1 Diabetes Enroll in the Living WIth Type 2 Diabetes ... Low-Calorie Sweeteners Sugar and Desserts Fitness Exercise & Type 1 Diabetes Get Started Safely Get And Stay Fit Types ...

  15. Types of Diabetes

    Science.gov (United States)

    ... Diabetes & Sexual & Urologic Problems Clinical Trials What is Diabetes? Diabetes is a disease that occurs when your ... is serious. What are the different types of diabetes? The most common types of diabetes are type ...

  16. Type 1 diabetes

    Science.gov (United States)

    Insulin-dependent diabetes; Juvenile onset diabetes; Diabetes - type 1; High blood sugar - type 1 diabetes ... Type 1 diabetes can occur at any age. It is most often diagnosed in children, adolescents, or young adults. Insulin is ...

  17. Guarded Cubical Type Theory

    DEFF Research Database (Denmark)

    Birkedal, Lars; Bizjak, Aleš; Clouston, Ranald

    2016-01-01

    terms. CTT provides a computational interpretation of functional extensionality, enjoys canonicity for the natural numbers type, and is conjectured to support decidable type-checking. Our new type theory, guarded cubical type theory (GCTT), provides a computational interpretation of extensionality......This paper improves the treatment of equality in guarded dependent type theory (GDTT), by combining it with cubical type theory (CTT). GDTT is an extensional type theory with guarded recursive types, which are useful for building models of program logics, and for programming and reasoning...... with coinductive types. We wish to implement GDTT with decidable type checking, while still supporting non-trivial equality proofs that reason about the extensions of guarded recursive constructions. CTT is a variation of Martin-L\\"of type theory in which the identity type is replaced by abstract paths between...

  18. Facts about Type 2

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    Full Text Available ... Ways to Give Close Are You at Risk? Home Prevention Diagnosing Diabetes and Learning About Prediabetes Type ... To Know Your Risk Alert Day Diabetes Basics Home Symptoms Diagnosis America's Diabetes Challenge Type 1 Type ...

  19. Types of Breast Pumps

    Science.gov (United States)

    ... Devices Consumer Products Breast Pumps Types of Breast Pumps Share Tweet Linkedin Pin it More sharing options ... used for feeding a baby. Types of Breast Pumps There are three basic types of breast pumps: ...

  20. Different Types of Lupus

    Science.gov (United States)

    ... Donate Share on Twitter Facebook Pinterest Email Print Different types of lupus Lupus Foundation of America September 18, 2017 Resource Content There are four different types of lupus. Learn more about each type ...

  1. Facts about Type 2

    Medline Plus

    Full Text Available ... a Member Donate Now! One Time Monthly In Memory In Honor Become a Member En Español Type 1 Type ... Diagnosing Diabetes and Learning About Prediabetes Type 2 Diabetes Risk Test Lower ...

  2. Facts about Type 2

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    Full Text Available ... Day Diabetes Basics Home Symptoms Diagnosis America's Diabetes Challenge Type 1 Type 2 Facts About Type 2 ... eating and being active. But, your doctor may need to also prescribe oral medications or insulin to ...

  3. Facts about Type 2

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    Full Text Available ... En Español Type 1 Type 2 About Us Online Community Meal Planning Sign In Search: Search More ... Diagnosing Diabetes and Learning About Prediabetes Type 2 Diabetes Risk Test Lower ...

  4. Type I Versus Type II Endometrial Cancer

    DEFF Research Database (Denmark)

    Noer, Mette Calundann; Antonsen, Sofie Leisby; Ottesen, Bent

    2018-01-01

    OBJECTIVE: Two distinct types of endometrial carcinoma (EC) with different etiology, tumor characteristics, and prognosis are recognized. We investigated if the prognostic impact of comorbidity varies between these 2 types of EC. Furthermore, we studied if the recently developed ovarian cancer....... A consistent association between increasing levels of comorbidity and poorer survival was observed for both types. Cox regression analyses revealed a significant interaction between cancer stage and comorbidity indicating that the impact of comorbidity varied with stage. In contrast, the interaction between...

  5. Guarded Cubical Type Theory

    DEFF Research Database (Denmark)

    Birkedal, Lars; Bizjak, Aleš; Clouston, Ranald

    2016-01-01

    types. This further expands the foundations of CTT as a basis for formalisation in mathematics and computer science. We present examples to demonstrate the expressivity of our type theory, all of which have been checked using a prototype type-checker implementation, and present semantics in a presheaf......This paper improves the treatment of equality in guarded dependent type theory (GDTT), by combining it with cubical type theory (CTT). GDTT is an extensional type theory with guarded recursive types, which are useful for building models of program logics, and for programming and reasoning...... with coinductive types. We wish to implement GDTT with decidable type-checking, while still supporting non-trivial equality proofs that reason about the extensions of guarded recursive constructions. CTT is a variation of Martin-L\\"of type theory in which the identity type is replaced by abstract paths between...

  6. Types and Automata

    DEFF Research Database (Denmark)

    Schwartzbach, Michael Ignatieff; Meineche Smidt, Erik

    A hierarchical type system for imperative programming languages gives rise to various computational problems, such as type equivalence, type ordering, etc. We present a particular class of finite automata which are shown to be isomorphic to type equations. All the relevant type concepts turn out...... to have well-known automata analogues, such as language equality, language inclusion, etc. This provides optimal or best known algorithms for the type system, by a process of translating type equations to automata, solving the analogous problem, and translating the result back to type equations. Apart...... from suggesting an implementation, this connection lends a certain naturality to our type system. We also introduce a very general form of extended (recursive) type equations which are explained in terms of (monotone) alternating automata. Since types are simply equationally defined trees...

  7. Type checking with open type functions

    DEFF Research Database (Denmark)

    Schrijvers, Tom; Jones, Simon Peyton; Chakravarty, Manual

    2008-01-01

    We report on an extension of Haskell with open type-level functions and equality constraints that unifies earlier work on GADTs, functional dependencies, and associated types. The contribution of the paper is that we identify and characterise the key technical challenge of entailment checking...

  8. Supramolecular Structure and Functional Analysis of the Type III Secretion System in Pseudomonas fluorescens 2P24.

    Science.gov (United States)

    Liu, Ping; Zhang, Wei; Zhang, Li-Qun; Liu, Xingzhong; Wei, Hai-Lei

    2015-01-01

    The type III secretion system (T3SS) of plant and animal bacterial pathogens directs the secretion and injection of proteins into host cells. Some homologous genes of T3SS were found also in non-pathogenic bacteria, but the organization of its machinery and basic function are still unknown. In this study, we identified a T3SS gene cluster from the plant growth-promoting Pseudomonas fluorescens 2P24 and isolated the corresponding T3SS apparatus. The T3SS gene cluster of strain 2P24 is similar organizationally to that of pathogenic P. syringae, except that it lacks the regulator hrpR and the hrpK1 and hrpH genes, which are involved in translocation of proteins. Electron microscopy revealed that the T3SS supramolecular structure of strain 2P24 was comprised of two distinctive substructures: a long extracellular, filamentous pilus, and a membrane-embedded base. We show that strain 2P24 deploys a harpin homolog protein, RspZ1, to elicit a hypersensitive response when infiltrated into Nicotiana tabacum cv. xanthi leaves with protein that is partially purified, and by complementing the hrpZ1 mutation of pHIR11. The T3SS of strain 2P24 retained ability to secrete effectors, whereas its effector translocation activity appeared to be excessively lost. Mutation of the rscC gene from 2P24 T3SS abolished the secretion of effectors, but the general biocontrol properties were unaffected. Remarkably, strain 2P24 induced functional MAMP-triggered immunity that included a burst of reactive oxygen species, strong suppression of challenge cell death, and disease expansion, while it was not associated with the secretion functional T3SS.

  9. Supramolecular structure and functional analysis of the type III secretion system in Pseudomonas fluorescens 2P24

    Directory of Open Access Journals (Sweden)

    Ping eLiu

    2016-01-01

    Full Text Available The type III secretion system (T3SS of plant and animal bacterial pathogens directs the secretion and injection of proteins into host cells. Some homologous genes of T3SS were found also in nonpathogenic bacteria, but the organization of its machinery and basic function are still unknown. In this study, we identified a T3SS gene cluster from the plant growth-promoting Pseudomonas fluorescens 2P24 and isolated the corresponding T3SS apparatus. The T3SS gene cluster of strain 2P24 is similar organizationally to that of pathogenic P. syringae, except that it lacks the regulator hrpR and the hrpK1 and hrpH genes, which are involved in translocation of proteins. Electron microscopy revealed that the T3SS supramolecular structure of strain 2P24 was comprised of two distinctive substructures: a long extracellular, filamentous pilus and a membrane-embedded base. We show that strain 2P24 deploys a harpin homologue protein, RspZ1, to elicit a hypersensitive response when infiltrated into Nicotiana tabacum cv. xanthi leaves with protein that is partially purified, and by complementing the hrpZ1 mutation of pHIR11. The T3SS of strain 2P24 retained ability to secrete effectors, whereas its effector translocation activity appeared to be excessively lost. Mutation of the rscC gene from 2P24 T3SS abolished the secretion of effectors, but the general biocontrol properties were unaffected. Remarkably, strain 2P24 induced functional MAMP-triggered immunity that included a burst of reactive oxygen species, strong suppression of challenge cell death, and disease expansion, while it was not associated with the secretion functional T3SS.

  10. Type III effectors orchestrate a complex interplay between transcriptional networks to modify basal defence responses during pathogenesis and resistance.

    Science.gov (United States)

    Truman, William; de Zabala, Marta Torres; Grant, Murray

    2006-04-01

    To successfully infect a plant, bacterial pathogens inject a collection of Type III effector proteins (TTEs) directly into the plant cell that function to overcome basal defences and redirect host metabolism for nutrition and growth. We examined (i) the transcriptional dynamics of basal defence responses between Arabidopsis thaliana and Pseudomonas syringae and (ii) how basal defence is subsequently modulated by virulence factors during compatible interactions. A set of 96 genes displaying an early, sustained induction during basal defence was identified. These were also universally co-regulated following other bacterial basal resistance and non-host responses or following elicitor challenges. Eight hundred and eighty genes were conservatively identified as being modulated by TTEs within 12 h post-inoculation (hpi), 20% of which represented transcripts previously induced by the bacteria at 2 hpi. Significant over-representation of co-regulated transcripts encoding leucine rich repeat receptor proteins and protein phosphatases were, respectively, suppressed and induced 12 hpi. These data support a model in which the pathogen avoids detection through diminution of extracellular receptors and attenuation of kinase signalling pathways. Transcripts associated with several metabolic pathways, particularly plastid based primary carbon metabolism, pigment biosynthesis and aromatic amino acid metabolism, were significantly modified by the bacterial challenge at 12 hpi. Superimposed upon this basal response, virulence factors (most likely TTEs) targeted genes involved in phenylpropanoid biosynthesis, consistent with the abrogation of lignin deposition and other wall modifications likely to restrict the passage of nutrients and water to the invading bacteria. In contrast, some pathways associated with stress tolerance are transcriptionally induced at 12 hpi by TTEs.

  11. Fix Your Types

    Directory of Open Access Journals (Sweden)

    Sol Swords

    2015-09-01

    Full Text Available When using existing ACL2 datatype frameworks, many theorems require type hypotheses. These hypotheses slow down the theorem prover, are tedious to write, and are easy to forget. We describe a principled approach to types that provides strong type safety and execution efficiency while avoiding type hypotheses, and we present a library that automates this approach. Using this approach, types help you catch programming errors and then get out of the way of theorem proving.

  12. Multiparty symmetric sum types

    DEFF Research Database (Denmark)

    Nielsen, Lasse; Yoshida, Nobuko; Honda, Kohei

    2010-01-01

    This paper introduces a new theory of multiparty session types based on symmetric sum types, by which we can type non-deterministic orchestration choice behaviours. While the original branching type in session types can represent a choice made by a single participant and accepted by others...... determining how the session proceeds, the symmetric sum type represents a choice made by agreement among all the participants of a session. Such behaviour can be found in many practical systems, including collaborative workflow in healthcare systems for clinical practice guidelines (CPGs). Processes...... with the symmetric sums can be embedded into the original branching types using conductor processes. We show that this type-driven embedding preserves typability, satisfies semantic soundness and completeness, and meets the encodability criteria adapted to the typed setting. The theory leads to an efficient...

  13. Facts about Type 2

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    Full Text Available ... People Working to Stop Diabetes Common Terms Diabetes Statistics Infographics Living with Diabetes Home Recently Diagnosed Where ... Basics Symptoms Type 1 Type 2 Gestational Myths Statistics Common Terms Genetics Living With Diabetes Recently Diagnosed ...

  14. Facts about Type 2

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    Full Text Available ... Enroll in the Living WIth Type 2 Diabetes Program Gestational What is Gestational Diabetes? How to Treat ... Enroll in the Living WIth Type 2 Diabetes Program In It Together We Can Help Center for ...

  15. Preventing Type 2 Diabetes

    Science.gov (United States)

    ... Sexual & Urologic Problems Clinical Trials Preventing Type 2 Diabetes Perhaps you have learned that you have a ... I lower my chances of developing type 2 diabetes? Research such as the Diabetes Prevention Program shows ...

  16. Facts about Type 2

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    Full Text Available ... Professional Books Patient Access to Research Student Resources History of Diabetes Resources for School Projects How to Reference ... Basics Symptoms Type 1 Type 2 Gestational Myths Statistics Common ... of Events Local Offices Volunteer Opportunities Signature Events Camps ...

  17. Types of Heart Failure

    Science.gov (United States)

    ... Venous Thromboembolism Aortic Aneurysm More Types of Heart Failure Updated:May 8,2017 Left-sided heart failure ... This content was last reviewed May 2017. Heart Failure • Home • About Heart Failure Introduction Types of Heart ...

  18. Blood Type Puzzle.

    Science.gov (United States)

    Kelly, Janet

    1997-01-01

    Presents a blood type puzzle that provides a visual, hands-on mechanism by which students can examine blood group reactions. Offers students an opportunity to construct their own knowledge about blood types. (JRH)

  19. Facts about Type 2

    Medline Plus

    Full Text Available ... Type 1 Type 2 About Us Online Community Meal Planning Sign In Search: Search ... Eating Overweight Smoking High Blood Pressure Physical Activity High Blood Glucose My Health ...

  20. Facts about Type 2

    Medline Plus

    Full Text Available ... Type 2 Diabetes Risk Test Lower Your Risk Healthy Eating Overweight Smoking High Blood Pressure Physical Activity High ... type 2 can control their blood glucose with healthy eating and being active. But, your doctor may need ...

  1. Facts about Type 2

    Medline Plus

    Full Text Available ... levels normal. Type 2 is treated with lifestyle changes, oral medications (pills), and insulin. When glucose builds ... It Together celebrates the steps you take Help change the conversation about type 2 diabetes. » « Connect With ...

  2. Haemophilus Influenzae Type b

    Science.gov (United States)

    ... Text Size Email Print Share Haemophilus Influenzae type b Page Content Article Body If you’re like ... may have been unfamiliar with Haemophilus influenzae type b (Hib) infections until your pediatrician recommended a vaccine ...

  3. Facts about Type 2

    Medline Plus

    Full Text Available ... Islanders, as well as the aged population. Patient Education Materials — Taking Care of Type 2 Diabetes This two-page introduction to type 2 diabetes is in PDF format so you can download it, print it, ...

  4. Types of Blood Donations

    Science.gov (United States)

    ... ill patients. Blood Donation 101 Blood Donation FAQs Types of Blood Donations The Foundation for America's Blood Centers Donate Blood Blood Donation 101 Blood Donation FAQs Types of Blood Donations About Blood What is Blood? ...

  5. Facts about Type 2

    Medline Plus

    Full Text Available ... En Español Type 1 Type 2 About Us Online Community Meal Planning Sign In Search: Search More ... Generation of Brilliant Researchers Diabetes Pro: Professional Resources Online We Support Your Doctor Clinical Practice Guidelines Patient ...

  6. Facts about Type 2

    Medline Plus

    Full Text Available ... Infographics Living with Diabetes Home Recently Diagnosed Where Do I Begin With Type2? Living With Type 1 ... Diabetes at School Tour de Cure Women's Series Do-It-Yourself Fundraising Become a Volunteer American Diabetes ...

  7. Facts about Type 2

    Medline Plus

    Full Text Available ... About Type 2 Recently Diagnosed Treatment and Care Blood Glucose Control Complications Medication Doctors, Nurses & More Enroll in the Living With Type 2 Diabetes Program donate en -- A Future Without Diabetes - a- ...

  8. Facts about Type 2

    Medline Plus

    Full Text Available ... or heart. Some people with type 2 can control their blood glucose with healthy eating and being active. But, your doctor may need to also prescribe oral medications or insulin to help you meet your target blood glucose ... type 2 diabetes than others. Type 2 diabetes is more common in African ...

  9. Type T Marital Therapy.

    Science.gov (United States)

    Farley, Frank; Carlson, Jon

    1991-01-01

    Briefly reviews Farley's Type T theory of personality and then considers a range of issues in marital therapy from the perspective of Type T. Suggests that Type T theory may be relevant in dealing with infidelity, sexual problems, love, marital abuse, child rearing, drug and alcohol use, money, division of household labor, recreation, and…

  10. Diabetes Type 2

    Science.gov (United States)

    Diabetes means your blood glucose, or blood sugar, levels are too high. With type 2 diabetes, the more common type, your body does not ... You have a higher risk of type 2 diabetes if you are older, have obesity, have a ...

  11. Osteogenesis imperfecta type V

    DEFF Research Database (Denmark)

    Rauch, Frank; Moffatt, Pierre; Cheung, Moira

    2013-01-01

    Osteogenesis imperfecta (OI) type V is an autosomal dominant bone fragility disorder that we had described a decade ago. Recent research has shown that OI type V is caused by a recurrent c.-14C>T mutation in IFITM5. In the present study, we assessed all patients diagnosed with OI type V at our...

  12. Facts about Type 2

    Medline Plus

    Full Text Available ... or insulin to help you meet your target blood glucose levels. Type 2 usually gets worse over time – even if ... About Type 2 Recently Diagnosed Treatment and Care Blood Glucose ... Living With Type 2 Diabetes Program donate en -- A Future Without ...

  13. Facts about Type 2

    Medline Plus

    Full Text Available ... from Diabetes Forecast® magazine: lp-type-2, . In this section Diabetes Basics Type 2 Facts About Type ... Your Stress-Free System for Family Dinners! A year of delicious meals to help prevent and manage ...

  14. Facts about Type 2

    Medline Plus

    Full Text Available ... Home Prevention Diagnosing Diabetes and Learning About Prediabetes Type 2 Diabetes Risk Test Lower Your Risk Healthy Eating Overweight ... About Type 2 Enroll in the Living WIth Type 2 Diabetes Program Gestational What is Gestational Diabetes? How to ...

  15. Facts about Type 2

    Medline Plus

    Full Text Available ... or insulin to help you meet your target blood glucose levels. Type 2 usually gets worse over time – even if ... About Type 2 Recently Diagnosed Treatment and Care Blood Glucose ... the Living With Type 2 Diabetes Program donate en -- A Future Without ...

  16. Type B Drum packages

    International Nuclear Information System (INIS)

    Edwards, W.S.

    1995-11-01

    The Type B Drum package is a container in which a single drum containing Type B quantities of radioactive material will be packaged for shipment. The Type B Drum containers are being developed to fill a void in the packaging and transportation capabilities of the US Department of Energy (DOE), as no double containment packaging for single drums of Type B radioactive material is currently available. Several multiple-drum containers and shielded casks presently exist. However, the size and weight of these containers present multiple operational challenges for single-drum shipments. The Type B Drum containers will offer one unshielded version and, if needed, two shielded versions, and will provide for the option of either single or double containment. The primary users of the Type B Drum container will be any organization with a need to ship single drums of Type B radioactive material. Those users include laboratories, waste retrieval facilities, emergency response teams, and small facilities

  17. TypeSan : Practical type confusion detection

    NARCIS (Netherlands)

    Haller, Istvan; Jeon, Yuseok; Peng, Hui; Payer, Mathias; Giuffrida, Cristiano; Bos, Herbert; Van Der Kouwe, Erik

    2016-01-01

    The low-level C++ programming language is ubiquitously used for its modularity and performance. Typecasting is a fundamental concept in C++ (and object-oriented programming in general) to convert a pointer from one object type into another. However, downcasting (converting a base class pointer to a

  18. Direct and Indirect Targeting of PP2A by Conserved Bacterial Type-III Effector Proteins.

    Directory of Open Access Journals (Sweden)

    Lin Jin

    2016-05-01

    Full Text Available Bacterial AvrE-family Type-III effector proteins (T3Es contribute significantly to the virulence of plant-pathogenic species of Pseudomonas, Pantoea, Ralstonia, Erwinia, Dickeya and Pectobacterium, with hosts ranging from monocots to dicots. However, the mode of action of AvrE-family T3Es remains enigmatic, due in large part to their toxicity when expressed in plant or yeast cells. To search for targets of WtsE, an AvrE-family T3E from the maize pathogen Pantoea stewartii subsp. stewartii, we employed a yeast-two-hybrid screen with non-lethal fragments of WtsE and a synthetic genetic array with full-length WtsE. Together these screens indicate that WtsE targets maize protein phosphatase 2A (PP2A heterotrimeric enzyme complexes via direct interaction with B' regulatory subunits. AvrE1, another AvrE-family T3E from Pseudomonas syringae pv. tomato strain DC3000 (Pto DC3000, associates with specific PP2A B' subunit proteins from its susceptible host Arabidopsis that are homologous to the maize B' subunits shown to interact with WtsE. Additionally, AvrE1 was observed to associate with the WtsE-interacting maize proteins, indicating that PP2A B' subunits are likely conserved targets of AvrE-family T3Es. Notably, the ability of AvrE1 to promote bacterial growth and/or suppress callose deposition was compromised in Arabidopsis plants with mutations of PP2A genes. Also, chemical inhibition of PP2A activity blocked the virulence activity of both WtsE and AvrE1 in planta. The function of HopM1, a Pto DC3000 T3E that is functionally redundant to AvrE1, was also impaired in specific PP2A mutant lines, although no direct interaction with B' subunits was observed. These results indicate that sub-component specific PP2A complexes are targeted by bacterial T3Es, including direct targeting by members of the widely conserved AvrE-family.

  19. Mastering TypeScript

    CERN Document Server

    Rozentals, Nathan

    2015-01-01

    Whether you are a JavaScript developer aiming to learn TypeScript, or an experienced TypeScript developer wanting to take your skills to the next level, this book is for you. From basic to advanced language constructs, test-driven development, and object-oriented techniques, you will learn how to get the most out of the TypeScript language.

  20. TypeScript revealed

    CERN Document Server

    Maharry, Dan

    2013-01-01

    TypeScript Revealed is a quick 100-page guide to Anders Hejlsberg's new take on JavaScript. With this brief, fast-paced introduction to TypeScript, .NET, Web and Windows 8 application developers who are already familiar with JavaScript will easily get up to speed with TypeScript and decide whether or not to start incorporating it into their own development. TypeScript is 'JavaScript for Application-scale development'; a superset of JavaScript that brings to it an additional object-oriented-like syntax familiar to .NET programmers that compiles down into simple, clean JavaScript that any browse

  1. Type Ia Supernova Cosmology

    Science.gov (United States)

    Leibundgut, B.; Sullivan, M.

    2018-03-01

    The primary agent for Type Ia supernova cosmology is the uniformity of their appearance. We present the current status, achievements and uncertainties. The Hubble constant and the expansion history of the universe are key measurements provided by Type Ia supernovae. They were also instrumental in showing time dilation, which is a direct observational signature of expansion. Connections to explosion physics are made in the context of potential improvements of the quality of Type Ia supernovae as distance indicators. The coming years will see large efforts to use Type Ia supernovae to characterise dark energy.

  2. Facts about Type 2

    Medline Plus

    Full Text Available ... CHIP For Parents & Kids Safe at School Everyday Life Children and Type 2 Diabetes Know Your Rights Employment Discrimination Health Care Professionals Law Enforcement Driver's ...

  3. Facts about Type 2

    Medline Plus

    Full Text Available ... Diagnosing Diabetes and Learning About Prediabetes Type 2 Diabetes Risk Test Lower Your Risk Healthy Eating Overweight Smoking High Blood Pressure Physical Activity High Blood ...

  4. Facts about Type 2

    Medline Plus

    Full Text Available ... or insulin to help you meet your target blood glucose levels. Type 2 usually gets worse over time – even if you don’t need medications at first, you may need to later on. Some groups have a higher risk for developing type 2 ...

  5. Flash-Type Discrimination

    Science.gov (United States)

    Koshak, William J.

    2010-01-01

    This viewgraph presentation describes the significant progress made in the flash-type discrimination algorithm development. The contents include: 1) Highlights of Progress for GLM-R3 Flash-Type discrimination Algorithm Development; 2) Maximum Group Area (MGA) Data; 3) Retrieval Errors from Simulations; and 4) Preliminary Global-scale Retrieval.

  6. Facts about Type 2

    Medline Plus

    Full Text Available ... A A A Listen En Español Facts About Type 2 Type 2 diabetes is the most common ... 5% back to the Association. Shopdiabetes.org: Your Stress-Free System for Family Dinners! - 2017-03-book- ...

  7. Facts about Type 2

    Medline Plus

    Full Text Available ... A A Listen En Español Facts About Type 2 Type 2 diabetes is the most common form ... program will help you live well. More from diabetes.org Healthy Recipes: Delicious Recipe Kits Delivered - 2017- ...

  8. Diabetes Type 1

    Science.gov (United States)

    Diabetes means your blood glucose, or blood sugar, levels are too high. With type 1 diabetes, your pancreas does not make insulin. Insulin is ... kidneys, nerves, and gums and teeth. Type 1 diabetes happens most often in children and young adults ...

  9. Types of Anesthesia

    Science.gov (United States)

    ... Videos for Educators Search English Español Types of Anesthesia KidsHealth / For Teens / Types of Anesthesia What's in ... Get? Print en español Tipos de anestesia About Anesthesia Anesthesia is broken down into three main categories: ...

  10. Facts about Type 2

    Medline Plus

    Full Text Available ... En Español Type 1 Type 2 About Us Online Community Meal Planning Sign In Search: Search More Sites Search ≡ Are You At Risk? Diabetes Basics Living with Diabetes Food & Fitness In My Community Advocacy Research & Practice Ways to Give Close Are You at ...

  11. Facts about Type 2

    Medline Plus

    Full Text Available ... En Español Type 1 Type 2 About Us Online Community Meal Planning Sign In Search: Search More Sites ... Twitter Pinterest Youtube Instagram Diabetes Stops Here Blog Online Community Site Menu Are You at Risk? Diagnosis Lower ...

  12. Improving Precision of Types

    DEFF Research Database (Denmark)

    Winther, Johnni

    mixing of unrelated types. Secondly, we present an improvement of the type checking algorithm in Java which enables the compiler to detect and ease the use of a common programming idiom called guarded casts. Thirdly, we present an improvement of the precision with which classes generated by a parser...

  13. Facts about Type 2

    Medline Plus

    Full Text Available ... Care of Type 2 Diabetes This two-page introduction to type 2 diabetes is in PDF format ... to the Association. Shopdiabetes.org: Your Stress-Free System for Family Dinners! - 2017-03-book-oclock-scramble. ...

  14. Facts about Type 2

    Medline Plus

    Full Text Available ... is the most common form of diabetes. In type 2 diabetes, your body does not use insulin properly. This is called insulin resistance. At first, ... insulin to keep your blood glucose levels normal. Type 2 is treated with lifestyle ... (pills), and insulin. When glucose builds up in the blood instead ...

  15. Beyond Type D personality

    DEFF Research Database (Denmark)

    Pelle, Aline J; Pedersen, Susanne S.; Szabó, Balázs M

    2009-01-01

    Type D personality has been associated with impaired health status in chronic heart failure (CHF), but other psychological factors may also be important.......Type D personality has been associated with impaired health status in chronic heart failure (CHF), but other psychological factors may also be important....

  16. Type Inference with Inequalities

    DEFF Research Database (Denmark)

    Schwartzbach, Michael Ignatieff

    1991-01-01

    of (monotonic) inequalities on the types of variables and expressions. A general result about systems of inequalities over semilattices yields a solvable form. We distinguish between deciding typability (the existence of solutions) and type inference (the computation of a minimal solution). In our case, both...

  17. Multiparty Asynchronous Session Types

    DEFF Research Database (Denmark)

    Honda, Kohei; Yoshida, Nobuko; Carbone, Marco

    2016-01-01

    Communication is a central elements in software development. As a potential typed foundation for structured communication-centered programming, session types have been studied over the past decade for a wide range of process calculi and programming languages, focusing on binary (two-party) sessio...

  18. Facts about Type 2

    Medline Plus

    Full Text Available ... Type 1 Type 2 About Us Online Community Meal Planning Sign In Search: Search More Sites Search ≡ ... Home Food MyFoodAdvisor Recipes Association Cookbook Recipes Planning Meals Diabetes Meal Plans Create Your Plate Gluten Free ...

  19. Facts about Type 2

    Medline Plus

    Full Text Available ... a Member Donate Now! One Time Monthly In Memory In Honor Become a Member En Español Type 1 Type 2 About Us Online Community Meal Planning Sign In Search: Search More Sites Search ≡ Are You At Risk? Diabetes Basics Living with Diabetes Food & Fitness In My Community Advocacy Research & Practice Ways ...

  20. Molecular Typing and Differentiation

    Science.gov (United States)

    In this chapter, general background and bench protocols are provided for a number of molecular typing techniques in common use today. Methods for the molecular typing and differentiation of microorganisms began to be widely adopted following the development of the polymerase chai...

  1. Facts about Type 2

    Medline Plus

    Full Text Available ... 2383) Give by Mail Close www.diabetes.org > Diabetes Basics > Type 2 Share: Print Page Text Size: A A A ... 2 diabetes is the most common form of diabetes. In type 2 diabetes, your body does not use insulin properly. ...

  2. Typing polymorphic recursion

    OpenAIRE

    Figueiredo, Lucília Camarão de; Camarão, Carlos

    2001-01-01

    This paper discusses some advantages of supporting polymorphic recursión in programming languages and describes a decidable type inference algorithm for typing polymorphic and possibly mutually recursive definitions, using Haskell to provide an executable high level specification of the algorithm.

  3. Facts about Type 2

    Medline Plus

    Full Text Available ... Type 2 Diabetes Program donate en -- #GiveForDiabetes - givefordiabetes.html #GiveForDiabetes Every 21 seconds, someone is diagnosed with ... Donate Today We Can Help - we-can-help.html Chat Online Chat Closed engagement en -- Free Type ...

  4. Facts about Type 2

    Medline Plus

    Full Text Available ... A A Listen En Español Facts About Type 2 Type 2 diabetes is the most common form ... Your Stress-Free System for Family Dinners! A year of delicious meals to help prevent and manage ...

  5. Personality types of dentists.

    Science.gov (United States)

    Westerman, G H; Grandy, T G; Erskine, C G

    1991-12-01

    The Myers-Briggs Type Indicator (MBTI) was used to determine the personality types of dental graduates, 1964-1984, from Creighton University, School of Dentistry. The MBTI reveals the strength and nature of preferences along four dimensions: extraversion-introversion, sensing-intuition, thinking-feeling, and judging-perceptive. In sample (N = 472), four personality types: ISTJ (108), ESTJ (66), ISFJ (48), and ENTJ (37), accounted for 54.9% (N = 259) of the dentists. The remaining 45.1% (N = 213) were divided among 12 personality types without any type accounting for more than 6.1% (N = 29). Comparisons with a general population (N = 9,320) revealed that the dental sample included more introverts (58.9%), thinkers (65.9%) and judgers (75.0%). The implications of personality characteristics, as applied to dentistry through communication patterns, relationships with co-workers and management styles were discussed.

  6. Personality types of entrepreneurs.

    Science.gov (United States)

    Müller, Günter F; Gappisch, Cathrin

    2005-06-01

    85 German entrepreneurs were psychometrically assessed on 12 primary trait characteristics. The sample consisted of 49 men and 36 women whose mean age was 45.6 yr. (SD= 10.3). Occupational domains were production (40%) and services (60%). The mean duration of entrepreneurship within these domains was 13.1 yr. (SD=9.3). By factor analysis five personality types of entrepreneurs could be identified: Creative Acquisitor, Controlled Perseverator, Distant Achiever, Rational Manager, and Egocentric Agitator. These types correspond with types found in research by Miner and with the Myer-Briggs Indicator. In addition, correlations between general type potential and both job and life satisfaction of entrepreneurs were found. The results are discussed with regard to intercultural stability of personality types and implications for research and application.

  7. Type 2 diabetes models

    DEFF Research Database (Denmark)

    Gram, Dorte Xenia

    2012-01-01

    This chapter deals with type 2 diabetes in vivo models and techniques suitable for testing new anti-diabetic compounds. In particular, the testing of TRP antagonist for beneficial effects against type 2 diabetes is considered. There are many choices of both in vitro techniques and in vivo models......, impaired glucose tolerance, impaired insulin secretion, and insulin resistance in vivo and should, thus, be sufficient to demonstrate preclinical proof of concept of a TRP antagonist in type 2 diabetes in rodents. The experiments are suggestions and could be replaced or supplemented by others....

  8. Parametric compositional data types

    DEFF Research Database (Denmark)

    Bahr, Patrick; Hvitved, Tom

    2012-01-01

    of recursive data types and functions on them in a modular and extendable fashion. Although CDTs provide a powerful tool for analysing and manipulating ASTs, they lack a convenient representation of variable binders. In this paper we remedy this deficiency by combining the framework of CDTs with Chlipala......In previous work we have illustrated the benefits that compositional data types (CDTs) offer for implementing languages and in general for dealing with abstract syntax trees (ASTs). Based on Swierstra's data types \\'a la carte, CDTs are implemented as a Haskell library that enables the definition...

  9. Griscelli syndrome type-3

    Directory of Open Access Journals (Sweden)

    Bela J Shah

    2016-01-01

    Full Text Available Griscelli syndrome (GS is a rare autosomal recessive multisystem disorder of pigmentary dilution of skin, silver gray hair, variable immunodeficiency, neurological impairment, and abnormal accumulation of melanosomes in melanocytes. GS type 3 is characterized by hypomelanosis with no immunological and neurological manifestation. Prognosis is very good in type 3 GS and usually require no active intervention, as opposed to type 1 and 2 where early diagnosis and treatment plays a crucial role in patient's survival. The characteristic phenotypic appearance, especially the pigment dilution of the patient's hair, is emphasized here.

  10. Action Type Deontic Logic

    DEFF Research Database (Denmark)

    Bentzen, Martin Mose

    2014-01-01

    A new deontic logic, Action Type Deontic Logic, is presented. To motivate this logic, a number of benchmark cases are shown, representing inferences a deontic logic should validate. Some of the benchmark cases are singled out for further comments and some formal approaches to deontic reasoning...... are evaluated with respect to the benchmark cases. After that follows an informal introduction to the ideas behind the formal semantics, focussing on the distinction between action types and action tokens. Then the syntax and semantics of Action Type Deontic Logic is presented and it is shown to meet...

  11. Facts about Type 2

    Medline Plus

    Full Text Available ... Safely Get And Stay Fit Types of Activity Weight Loss Assess Your Lifestyle Getting Started Food Choices In ... Food Recipes Planning Meals What Can I Eat Weight Loss Fitness In My Community Calendar of Events Local ...

  12. Facts about Type 2

    Medline Plus

    Full Text Available ... Types of Carbohydrates Carbohydrate Counting Make Your Carbs Count Glycemic Index Low-Calorie Sweeteners Sugar and Desserts ... their blood glucose with healthy eating and being active. But, your doctor may need to also prescribe ...

  13. Facts about Type 2

    Medline Plus

    Full Text Available ... Medicare Medicaid & CHIP For Parents & Kids Safe at School Everyday Life Children and Type 2 Diabetes Know ... Cure Father of the Year Stop Diabetes at School Tour de Cure Women's Series Do-It-Yourself ...

  14. Facts about Type 2

    Medline Plus

    Full Text Available ... a Member Donate Now! One Time Monthly In Memory In Honor Become a Member En Español Type ... time Give monthly Give in honor Give in memory Donate Now Why Give? Nearly 30 million battle ...

  15. Facts about Type 2

    Medline Plus

    Full Text Available ... Type 2 Diabetes Know Your Rights Employment Discrimination Health Care Professionals Law Enforcement Driver's License For Lawyers Food & ... Terms Genetics Living With Diabetes Recently Diagnosed Treatment & Care Complications Health Insurance For Parents & Kids Know Your Rights We ...

  16. Type 1 diabetes

    DEFF Research Database (Denmark)

    Green, Anders; Kyvik, Kirsten Ohm

    2001-01-01

    Prediction of Type 1 diabetes at individual level is relevant for any possible intervention before clinical disease develops. Currently available markers of Type 1 diabetes include genetic specificities and immune markers, in addition to a positive family history. This chapter reviews the measures...... and methods of importance in predicting Type 1 diabetes. Based on numerical examples it is demonstrated that available markers have a low level of performance, even when combined. Even so, combined marker information may allow for the identification of the large majority of the general population who...... is at very low disease risk. The impact at population level of predicting Type 1 diabetes varies between societies because the performance of markers depends on levels of disease risk and distribution of markers within a population. The incorporation of the influence of non-genetic etiological factors may...

  17. Facts about Type 2

    Medline Plus

    Full Text Available ... Risk Healthy Eating Overweight Smoking High Blood Pressure Physical Activity High Blood Glucose My Health Advisor Tools To Know Your Risk Alert Day Diabetes Basics Home Symptoms Diagnosis America's Diabetes Challenge Type ...

  18. Facts about Type 2

    Medline Plus

    Full Text Available ... Health Insurance Update The Health Insurance Marketplace Health Insurance From an Employer Options for the Uninsured Medicare Medicaid & CHIP For Parents & Kids Safe at School Everyday Life Children and Type 2 Diabetes Know Your Rights ...

  19. Facts about Type 2

    Medline Plus

    Full Text Available ... Prediabetes Type 2 Diabetes Risk Test Lower Your Risk Healthy Eating Overweight Smoking High Blood Pressure Physical Activity High Blood Glucose My Health Advisor Tools To Know Your Risk Alert Day Diabetes Basics Home Symptoms Diagnosis America's ...

  20. Facts about Type 2

    Medline Plus

    Full Text Available ... for Association Events Messaging Tools Recruiting Advocates Local Market Planning Training Webinars News & Events Advocacy News Call ... others. Type 2 diabetes is more common in African Americans, Latinos, Native Americans, and Asian Americans/Pacific Islanders, ...

  1. Facts about Type 2

    Medline Plus

    Full Text Available ... medications or insulin to help you meet your target blood glucose levels. Type 2 usually gets worse ... Advocacy Take Action Advocacy Priorities News & Events The Cost of Diabetes Advocate Toolkit Call to Congress Research & ...

  2. Facts about Type 2

    Medline Plus

    Full Text Available ... Doctors, Nurses & More Oral Health & Hygiene Women A1C Insulin Pregnancy 8 Tips for Caregivers Health Insurance Health ... type 2 diabetes, your body does not use insulin properly. This is called insulin resistance. At first, ...

  3. Facts about Type 2

    Medline Plus

    Full Text Available ... Are Research Leaders World's Largest Diabetes Meeting Recent Advances Type 1 Research Highlights Research Excellence Honorees How ... up in the blood instead of going into cells, it can cause two problems: Right away, your ...

  4. Facts about Type 2

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    Full Text Available ... to Give Close Are You at Risk? Home Prevention Diagnosing Diabetes and Learning About Prediabetes Type 2 Diabetes Risk Test Lower Your Risk Healthy Eating Overweight Smoking High Blood Pressure Physical Activity High Blood Glucose ...

  5. Facts about Type 2

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    Full Text Available ... Children and Type 2 Diabetes Know Your Rights Employment Discrimination Health Care Professionals Law Enforcement Driver's License ... Find Your Local Office Find your local diabetes education program Calendar of Events Wellness Lives Here Awareness ...

  6. Facts about Type 2

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    Full Text Available ... Risk Healthy Eating Overweight Smoking High Blood Pressure Physical Activity High Blood Glucose My Health Advisor Tools To ... Asian Americans/Pacific Islanders, as well as the aged population. Patient Education Materials — Taking Care of Type ...

  7. Facts about Type 2

    Medline Plus

    Full Text Available ... Life Children and Type 2 Diabetes Know Your Rights Employment Discrimination Health Care Professionals Law Enforcement Driver's ... going into cells, it can cause two problems: Right away, your cells may be starved for energy. ...

  8. Facts about Type 2

    Medline Plus

    Full Text Available ... Healthy Eating Overweight Smoking High Blood Pressure Physical Activity High Blood Glucose My Health Advisor Tools To ... Started Safely Get And Stay Fit Types of Activity Weight Loss Assess Your Lifestyle Getting Started Food ...

  9. Facts about Type 2

    Medline Plus

    Full Text Available ... Practice Ways to Give Close Are You at Risk? Home Prevention Diagnosing Diabetes and Learning About Prediabetes Type 2 Diabetes Risk Test Lower Your Risk Healthy Eating Overweight Smoking ...

  10. Facts about Type 2

    Medline Plus

    Full Text Available ... Diabetes Risk Test Lower Your Risk Healthy Eating Overweight Smoking High Blood Pressure Physical Activity High Blood ... For Parents & Kids Safe at School Everyday Life Children and Type 2 Diabetes Know Your Rights Employment ...

  11. Facts about Type 2

    Medline Plus

    Full Text Available ... the Living WIth Type 2 Diabetes Program Gestational What is Gestational Diabetes? How to Treat Gestational Diabetes ... Cook with Heart-Healthy Foods Holiday Meal Planning What Can I Eat? Making Healthy Food Choices Diabetes ...

  12. Types of Pesticide Ingredients

    Science.gov (United States)

    Pesticide active ingredients are described by the types of pests they control or how they work. For example, algicides kill algae, biopesticides are derived from natural materials, and insecticides kill insects.

  13. Facts about Type 2

    Medline Plus

    Full Text Available ... Treatment and Care Blood Glucose Control Complications Medication Doctors, Nurses & More Enroll in the Living With Type 2 Diabetes Program donate en -- A Future Without Diabetes - a-future- ...

  14. [Types of insulin therapy].

    Science.gov (United States)

    Sáez de la Fuente, J; Granja Berna, V; Ferrari Piquero, J M; Valero Zanuy, M A; Herreros de Tejada López-Coterilla, A

    2008-02-01

    Diabetes mellitus is a chronic disease associated with a series of long-term microvascular and macrovascular complications that requires continuing therapeutic control. In recent years, the pharmaceutical industry has developed new types of insulin and administration systems in order to more closely mimic human insulin secretion. In this way, insulin therapy is divided into conventional and intensive regimens according to their complexity. In type 1 diabetes mellitus (T1DM) patients, the treatment of choice is the one which achieves intensive glycemic control. In type 2 diabetes mellitus, we can start with a simplified conventional regimen which could progress into an intensive one similar to that of T1DM treatment. Both types of diabetes require an individualized treatment prescription based on the needs and characteristics of each patient.

  15. Facts about Type 2

    Medline Plus

    Full Text Available ... Index Low-Calorie Sweeteners Sugar and Desserts Fitness Exercise & Type 1 Diabetes Get Started Safely Get And ... Events Messaging Tools Recruiting Advocates Local Market Planning Training Webinars News & Events Advocacy News Call to Congress ...

  16. Facts about Type 2

    Medline Plus

    Full Text Available ... Prediabetes Type 2 Diabetes Risk Test Lower Your Risk Healthy Eating Overweight Smoking High Blood Pressure Physical Activity High Blood Glucose My Health Advisor Tools To Know Your Risk Alert Day ...

  17. Facts about Type 2

    Medline Plus

    Full Text Available ... Medicare Medicaid & CHIP For Parents & Kids Safe at School Everyday Life Children and Type 2 Diabetes Know ... Cure Father of the Year Stop Diabetes at School Tour de Cure Women's Series Destination Races Do- ...

  18. Facts about Type 2

    Medline Plus

    Full Text Available ... Diabetes Research & Practice Home We Are Research Leaders World's Largest Diabetes Meeting Recent Advances Type 1 Research ... help us get closer to curing diabetes and better treatments for those living with diabetes. Other Ways ...

  19. Facts about Type 2

    Medline Plus

    Full Text Available ... In type 2 diabetes, your body does not use insulin properly. This is called insulin resistance. At ... 1995-2018. American Diabetes Association. All rights reserved. Use of this website constitutes acceptance of our Terms ...

  20. Facts about Type 2

    Medline Plus

    Full Text Available ... Funding the Next Generation of Brilliant Researchers Diabetes Pro: Professional Resources Online We Support Your Doctor Clinical ... Type 2 Diabetes Recipes for Healthy Living Diabetes Pro: Professional Resources Shop Diabetes » Close nonprofit software

  1. Treating Type 2 Diabetes

    Science.gov (United States)

    ... type 2 diabetes need to: eat a healthy, balanced diet and follow a meal plan get regular exercise ... with scheduling meals and insulin injections. Remember, a balanced diet, regular physical activity, and a healthy weight can ...

  2. Facts about Type 2

    Medline Plus

    Full Text Available ... A Day in the Life of Diabetes Famous People Working to Stop Diabetes Common Terms Diabetes Statistics ... hurt your eyes, kidneys, nerves or heart. Some people with type 2 can control their blood glucose ...

  3. Facts about Type 2

    Medline Plus

    Full Text Available ... Diets Meal Planning for Vegetarian Diets Cook with Heart-Healthy Foods Holiday Meal Planning What Can I ... levels may hurt your eyes, kidneys, nerves or heart. Some people with type 2 can control their ...

  4. Facts about Type 2

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    Full Text Available ... year of delicious meals to help prevent and manage diabetes. Ask the Experts: Learn to Live Well ... It Together celebrates the steps you take Help change the conversation about type 2 diabetes. » « Connect With ...

  5. Facts about Type 2

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    Full Text Available ... and Learning About Prediabetes Type 2 Diabetes Risk Test Lower Your Risk Healthy Eating Overweight Smoking High ... You at Risk? Diagnosis Lower Your Risk Risk Test Alert Day Prediabetes My Health Advisor Tools to ...

  6. Facts about Type 2

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    Full Text Available ... and Learning About Prediabetes Type 2 Diabetes Risk Test Lower Your Risk Healthy Eating Overweight Smoking High Blood Pressure Physical Activity High Blood Glucose My Health Advisor Tools ...

  7. Facts about Type 2

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    Full Text Available ... or heart. Some people with type 2 can control their blood glucose with healthy eating and being ... 2 Recently Diagnosed Treatment and Care Blood Glucose Control Complications Medication Doctors, Nurses & More Enroll in the ...

  8. Facts about Type 2

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    Full Text Available ... Step On Up Treatment & Care Blood Glucose Testing Medication Doctors, Nurses & More Oral Health & Hygiene Women A1C ... Type 2 is treated with lifestyle changes, oral medications (pills), and insulin. When glucose builds up in ...

  9. Facts about Type 2

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    Full Text Available ... Right away, your cells may be starved for energy. Over time, high blood glucose levels may hurt ... lwt2d-en.html Have Type 2 Diabetes? Our free program will help you live well. More from ...

  10. Facts about Type 2

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    Full Text Available ... Type 2 About Us Online Community Meal Planning Sign In Search: Search More Sites Search ≡ Are You ... diabetes news, research and food & fitness tips. Email: Sign Up Thank you for signing up ' + ' '); $('.survey-form'). ...

  11. Tissue types (image)

    Science.gov (United States)

    There are 4 basic types of tissue: connective tissue, epithelial tissue, muscle tissue, and nervous tissue. Connective tissue ... and binds them together (bone, blood, and lymph tissues). Epithelial tissue provides a covering (skin, the linings of ...

  12. Facts about Type 2

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    Full Text Available ... Diabetes Research & Practice Home We Are Research Leaders World's Largest Diabetes Meeting Recent Advances Type 1 Research ... new is diagnosed. Diabetes causes more deaths a year than breast cancer and AIDS combined. Your gift ...

  13. Facts about Type 2

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  14. Facts about Type 2

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    Full Text Available ... Basics Living with Diabetes Food & Fitness In My Community Advocacy Research & Practice Ways to Give Close Are You at Risk? Home Prevention Diagnosing Diabetes and Learning About Prediabetes Type 2 Diabetes Risk Test Lower ...

  15. Facts about Type 2

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    Full Text Available ... 2 Enroll in the Living WIth Type 2 Diabetes Program Gestational What is Gestational Diabetes? How to Treat Gestational Diabetes Genetics of Diabetes Diabetes Myths A Day in ...

  16. Facts about Type 2

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    Full Text Available ... You at Risk? Home Prevention Diagnosing Diabetes and Learning About Prediabetes Type 2 Diabetes Risk Test Lower ... EXPO Volunteer Opportunities Sponsorship and Exhibit Opportunities Camp Learning at Camp Find a Camp Fundraising Events Step ...

  17. Facts about Type 2

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    Full Text Available ... 2 Diabetes Program Gestational What is Gestational Diabetes? How to Treat Gestational Diabetes Genetics of Diabetes Diabetes ... Advances Type 1 Research Highlights Research Excellence Honorees How We Fund Research Funding the Next Generation of ...

  18. Facts about Type 2

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    Full Text Available ... August 1, 2013 Last Edited: October 27, 2015 Articles from Diabetes Forecast® magazine: lp-type-2, . In ... Diabetes Pro: Professional Resources Shop Diabetes » Close nonprofit software

  19. Facts about Type 2

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  20. Facts about Type 2

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    Full Text Available ... Test Lower Your Risk Healthy Eating Overweight Smoking High Blood Pressure Physical Activity High Blood Glucose My Health Advisor ... Quick Meal Ideas Snacks Nutrient Content Claims Understanding Carbohydrates Types of Carbohydrates Carbohydrate Counting Make Your Carbs ...

  1. Facts about Type 2

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    Full Text Available ... People Working to Stop Diabetes Common Terms Diabetes Statistics Infographics ... Islanders, as well as the aged population. Patient Education Materials — Taking Care of Type 2 ...

  2. Types of OI

    Science.gov (United States)

    ... Unbreakable Spirit® OI Golf Classic Awareness Week Fine Wines Strong Bones Bone China Tea Blue Jeans for Better Bones Upcoming Events Online Store Facts About OI Types of OI Myths About OI OI ...

  3. Facts about Type 2

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    Full Text Available ... of Diabetes Diabetes Myths A Day in the Life of Diabetes Famous People Working to Stop Diabetes ... CHIP For Parents & Kids Safe at School Everyday Life Children and Type 2 Diabetes Know Your Rights ...

  4. Type Systems for Bigraphs

    DEFF Research Database (Denmark)

    Elsborg, Ebbe; Hildebrandt, Thomas; Sangiorgi, Davide

    is based on a fixed set of elementary bigraphs and operators on these. An essential elementary bigraph is an ion, to which a control can be attached modelling its kind (its ordered number of channels and whether it is a guard), e.g. an input prefix of pi-calculus. A model of a calculus is then a set......; and the possibility of modularly adapting the type systems to extensions of the BRS (with new controls). As proof of concept we present a model of a pi-calculus, develop an i/o-type system with subtyping on this model, prove crucial properties (including subject reduction) for this type system, and transfer...... these properties to the (typed) pi-calculus....

  5. Facts about Type 2

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    Full Text Available ... Professional Books Patient Access to Research Student Resources History of Diabetes Resources for School Projects How to ... Type 2 diabetes is more common in African Americans, Latinos, Native Americans, and Asian Americans/Pacific Islanders, ...

  6. Facts about Type 2

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    Full Text Available ... Diagnosing Diabetes and Learning About Prediabetes Type 2 Diabetes Risk Test Lower Your Risk Healthy Eating Overweight Smoking High Blood Pressure Physical Activity High Blood Glucose My Health Advisor ...

  7. Facts about Type 2

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    Full Text Available ... and Learning About Prediabetes Type 2 Diabetes Risk Test Lower Your Risk Healthy Eating Overweight Smoking High Blood Pressure Physical Activity High Blood Glucose My Health ...

  8. Facts about Type 2

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    Full Text Available ... Type 2 Diabetes Know Your Rights Employment Discrimination Health Care Professionals Law Enforcement Driver's License For Lawyers Food & Fitness Home Food MyFoodAdvisor Recipes Association Cookbook Recipes Planning ...

  9. Facts about Type 2

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    Full Text Available ... Safely Get And Stay Fit Types of Activity Weight Loss Assess Your Lifestyle Getting Started Food Choices ... Food Recipes Planning Meals What Can I Eat Weight Loss Fitness In My Community Calendar of Events ...

  10. Facts about Type 2

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    Full Text Available ... make enough insulin to keep your blood glucose levels normal. Type 2 is treated with lifestyle changes, ... starved for energy. Over time, high blood glucose levels may hurt your eyes, kidneys, nerves or heart. ...

  11. Facts about Type 2

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    Full Text Available ... and Learning About Prediabetes Type 2 Diabetes Risk Test Lower Your Risk Healthy Eating Overweight Smoking High ... excused. 86 million Americans have prediabetes. Take the test. Know where you stand. More from diabetes.org ...

  12. Facts about Type 2

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    Full Text Available ... is the most common form of diabetes. In type 2 diabetes, your body does not use insulin properly. This is called insulin resistance. At first, the pancreas makes extra insulin to ...

  13. Facts about Type 2

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    Full Text Available ... for the Uninsured Medicare Medicaid & CHIP For Parents & Kids Safe at School Everyday Life Children and Type ... Diagnosed Treatment & Care Complications Health Insurance For Parents & Kids Know Your Rights We Can Help Enroll in ...

  14. Facts about Type 2

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    Full Text Available ... for Association Events Messaging Tools Recruiting Advocates Local Market Planning Training Webinars News & Events Advocacy News Call ... medications or insulin to help you meet your target blood glucose levels. Type 2 usually gets worse ...

  15. Type extension trees

    DEFF Research Database (Denmark)

    Jaeger, Manfred

    2006-01-01

    We introduce type extension trees as a formal representation language for complex combinatorial features of relational data. Based on a very simple syntax this language provides a unified framework for expressing features as diverse as embedded subgraphs on the one hand, and marginal counts...... of attribute values on the other. We show by various examples how many existing relational data mining techniques can be expressed as the problem of constructing a type extension tree and a discriminant function....

  16. Type Families with Class, Type Classes with Family

    DEFF Research Database (Denmark)

    Serrano, Alejandro; Hage, Jurriaan; Bahr, Patrick

    2015-01-01

    Type classes and type families are key ingredients in Haskell programming. Type classes were introduced to deal with ad-hoc polymorphism, although with the introduction of functional dependencies, their use expanded to type-level programming. Type families also allow encoding type-level functions......, now as rewrite rules. This paper looks at the interplay of type classes and type families, and how to deal with shortcomings in both of them. Furthermore, we show how to use families to simulate classes at the type level. However, type families alone are not enough for simulating a central feature...

  17. Helical type vacuum container

    International Nuclear Information System (INIS)

    Owada, Kimio.

    1989-01-01

    Helical type vacuum containers in the prior art lack in considerations for thermal expansion stresses to helical coils, and there is a possibility of coil ruptures. The object of the present invention is to avoid the rupture of helical coils wound around the outer surface of a vacuum container against heat expansion if any. That is, bellows or heat expansion absorbing means are disposed to a cross section of a helical type vacuum container. With such a constitution, thermal expansion of helical coils per se due to temperature elevation of the coils during electric supply can be absorbed by expansion of the bellows or absorption of the heat expansion absorbing means. Further, this can be attained by arranging shear pins in the direction perpendicular to the bellows axis so that the bellows are not distorted when the helical coils are wound around the helical type vacuum container. (I.S.)

  18. Congenital fiber type disproportion.

    Science.gov (United States)

    Kissiedu, Juliana; Prayson, Richard A

    2016-04-01

    Type I muscle fiber atrophy in childhood can be encountered in a variety of neuromuscular disorders. Congenital fiber type disproportion (CFTD) is one such condition which presents as a nonprogressive muscle weakness. The diagnosis is often made after excluding other differential diagnostic considerations. We present a 2-year-9-month-old full term boy who presented at 2 months with an inability to turn his head to the right. Over the next couple of years, he showed signs of muscle weakness, broad based gait and a positive Gower's sign. He had normal levels of creatine kinase and normal electromyography. A biopsy of the vastus lateralis showed a marked variation in muscle fiber type. The adenosine triphosphate (ATP)-ase stains highlighted a marked type I muscle atrophy with rare scattered atrophic type II muscle fibers. No abnormalities were observed on the nicotinamide adenine dinucleotide (NADH), succinate dehydrogenase (SDH) or cytochrome oxidase stained sections. Ragged red fibers were not present on the trichrome stain. Abnormalities of glycogen or lipid deposition were not observed on the periodic acid-Schiff or Oil-Red-O stains. Immunostaining for muscular dystrophy associated proteins showed normal staining. Ultrastructural examination showed a normal arrangement of myofilaments, and a normal number and morphology for mitochondria. A diagnosis of CFTD was made after excluding other causes of type I atrophy including congenital myopathy. The lack of specific clinical and genetic disorder associated with CFTD suggests that it is a spectrum of a disease process and represents a diagnosis of exclusion. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Brauer type embedding problems

    CERN Document Server

    Ledet, Arne

    2005-01-01

    This monograph is concerned with Galois theoretical embedding problems of so-called Brauer type with a focus on 2-groups and on finding explicit criteria for solvability and explicit constructions of the solutions. The advantage of considering Brauer type embedding problems is their comparatively simple condition for solvability in the form of an obstruction in the Brauer group of the ground field. This book presupposes knowledge of classical Galois theory and the attendant algebra. Before considering questions of reducing the embedding problems and reformulating the solvability criteria, the

  20. Guarded Type Promotion

    DEFF Research Database (Denmark)

    Winther, Johnni

    2011-01-01

    In Java, explicit casts are ubiquitous since they bridge the gap between compile-time and runtime type safety. Since casts potentially throw a ClassCastException, many programmers use a defensive programming style of guarded casts. In this programming style casts are protected by a preceding...... in a Java 6 compiler. Through our extensive testing of real-life code we show that guarded casts account for approximately one fourth of all casts and that Guarded Type Promotion can eliminate the need for 95 percent of these guarded casts....

  1. Type Inference for Session Types in the Pi-Calculus

    DEFF Research Database (Denmark)

    Graversen, Eva Fajstrup; Harbo, Jacob Buchreitz; Huttel, Hans

    2014-01-01

    In this paper we present a direct algorithm for session type inference for the π-calculus. Type inference for session types has previously been achieved by either imposing limitations and restriction on the π-calculus, or by reducing the type inference problem to that for linear types. Our approach...

  2. Facts about Type 2

    Medline Plus

    Full Text Available ... 1 Type 2 About Us Online Community Meal Planning Sign In Search: Search More Sites Search ≡ Are ... Fitness Home Food MyFoodAdvisor Recipes Association Cookbook Recipes Planning Meals Diabetes Meal Plans Create Your Plate Gluten ...

  3. Types of Funerals

    Science.gov (United States)

    ... High-Speed Internet Service Shopping for Used Mattresses Solar Power for Your Home The FTC Funeral Rule The Language of Recycling Travel Tips Types of Funerals Using Layaway Plans Warranties You Are Here Bookmark Buying & Owning a Car Credit & Loans Dealing with Debt Resolving Consumer Problems ...

  4. Facts about Type 2

    Medline Plus

    Full Text Available ... Diagnosing Diabetes and Learning About Prediabetes Type 2 Diabetes Risk Test Lower Your Risk Healthy Eating Overweight Smoking High Blood Pressure Physical Activity High Blood Glucose My Health Advisor Tools To Know Your Risk Alert Day Diabetes Basics ...

  5. Facts about Type 2

    Medline Plus

    Full Text Available ... Care Blood Glucose Testing Medication Doctors, Nurses & More Oral Health & Hygiene Women A1C Insulin Pregnancy 8 Tips for ... But, your doctor may need to also prescribe oral medications or insulin to help you meet your target blood glucose levels. Type 2 usually gets ... Health Advisor Tools to Know Your Risk Diabetes Basics ...

  6. Chemistry of Blood Type

    Science.gov (United States)

    Coleman, William F.

    2005-01-01

    The molecule of December 2005 comes from the paper by Rose, Palcic and Evans on structural factors determining the blood type. The structure was previously reported by Palcic and Evans and is presented without the water molecule that is determined in the crystal structure.

  7. Facts about Type 2

    Medline Plus

    Full Text Available ... Care Blood Glucose Testing Medication Doctors, Nurses & More Oral Health & Hygiene Women A1C Insulin Pregnancy 8 Tips for ... But, your doctor may need to also prescribe oral medications or insulin to help you meet your target blood glucose levels. Type 2 usually gets worse ... Health Advisor Tools to Know Your Risk Diabetes Basics ...

  8. Making Type Inference Practical

    DEFF Research Database (Denmark)

    Schwartzbach, Michael Ignatieff; Oxhøj, Nicholas; Palsberg, Jens

    1992-01-01

    We present the implementation of a type inference algorithm for untyped object-oriented programs with inheritance, assignments, and late binding. The algorithm significantly improves our previous one, presented at OOPSLA'91, since it can handle collection classes, such as List, in a useful way. A......-oriented languages practical....

  9. Facts about Type 2

    Medline Plus

    Full Text Available ... Diabetes causes more deaths a year than breast cancer and AIDS combined. Your gift today will help us get closer ... time, high blood glucose levels may hurt your eyes, kidneys, nerves or heart. Some people with type 2 ...

  10. Facts about Type 2

    Medline Plus

    Full Text Available ... You at Risk? Home Prevention Diagnosing Diabetes and Learning About Prediabetes Type 2 Diabetes Risk Test Lower Your Risk Healthy Eating Overweight Smoking High Blood Pressure Physical Activity High Blood Glucose My Health Advisor Tools To Know Your Risk Alert Day Diabetes Basics ...

  11. Type VI secretion system.

    Science.gov (United States)

    Salomon, Dor; Orth, Kim

    2015-03-30

    Bacteria employ a variety of tools to survive in a competitive environment. Salomon and Orth describe one such tool-the Type 6 Secretion Systems used by bacteria to deliver a variety of toxins into competing cells. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. TypeScript essentials

    CERN Document Server

    Nance, Christopher

    2014-01-01

    The book introduces the TypeScript language and its features to anyone looking to develop rich web applications. Whether you are new to web development or are an experienced engineer with strong JavaScript skills, this book will get you writing code quickly. A basic understanding of JavaScript and its language features are necessary for this book.

  13. Plaque Type Eryrhema Nodosum

    Directory of Open Access Journals (Sweden)

    Radha Mittal

    1987-01-01

    Full Text Available Three young females developed plaque type erythema nodosum. The underlying causes in them were tuberculosis chest, recurrent furunculosis and malaria respectively. All the three cases were under treatment at the time of development of erythema nodosum plaques and the onset was acute.

  14. Facts about Type 2

    Medline Plus

    Full Text Available ... Edited: October 27, 2015 Articles from Diabetes Forecast® magazine: lp-type-2, . In this section Diabetes Basics ... up to ride in Tour de Cure and create your team today! More from diabetes.org Healthy ...

  15. Facts about Type 2

    Medline Plus

    Full Text Available ... lwt2d-en.html Have Type 2 Diabetes? Our free program will help you live well. More from diabetes.org Healthy Recipes: Delicious Recipe Kits Delivered - 2017-03-chefd.html Healthy Recipes Delicious ... Your Stress-Free System for Family Dinners! - 2017-03-book-oclock- ...

  16. Facts about Type 2

    Medline Plus

    Full Text Available ... Diabetes causes more deaths a year than breast cancer and AIDS combined. Your gift today will help us get closer to ... normal. Type 2 is treated with lifestyle changes, oral medications (pills), and insulin. When glucose builds up ...

  17. Facts about Type 2

    Medline Plus

    Full Text Available ... Complications Neuropathy Foot Complications DKA (Ketoacidosis) & Ketones Kidney Disease (Nephropathy) Gastroparesis Mental Health Step On Up Treatment & ... Non-starchy Vegetables Grains and Starchy ... form of diabetes. In type 2 diabetes, your body does not use insulin properly. This is called insulin resistance. At ...

  18. Facts about Type 2

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    Full Text Available ... the Living WIth Type 2 Diabetes Program Gestational What is Gestational Diabetes? How to Treat Gestational Diabetes Genetics of Diabetes Diabetes Myths A Day in the Life of Diabetes Famous People Working to Stop Diabetes Common Terms Diabetes Statistics Infographics ...

  19. Facts about Type 2

    Medline Plus

    Full Text Available ... diabetes. » « Connect With Us Register for diabetes news, research and food & fitness tips. Email: Sign Up Thank you for ... Living WIth Type 2 Diabetes Program Food & Fitness Food Recipes Planning ... to Congress Research & Practice We Are Research Leaders We Support Your ...

  20. Facts about Type 2

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    Full Text Available ... you may need to later on. Some groups have a higher risk for developing type 2 diabetes ... Online Chat Closed engagement en -- So…Do You Have Prediabetes? - 2017-01-ad-council.html So…Do ...

  1. Types of Timberland Ownership

    Science.gov (United States)

    William C. Siegel

    1999-01-01

    The form of ownership in which you hold your woodland is important from a tax standpoint. Further, if your forest property is structured as a business, the type of business organization chosen also has significant tax implications. Additionally, non-tax factors bear on choosing an ownership and/or business format. These include forest management goals, size of the...

  2. Compositional data types

    DEFF Research Database (Denmark)

    Bahr, Patrick; Hvitved, Tom

    2011-01-01

    -cut fusion style deforestation which yields considerable speedups. We demonstrate our framework in the setting of compiler construction, and moreover, we compare compositional data types with generic programming techniques and show that both are comparable in run-time performance and expressivity while our...

  3. Types of CMT

    Science.gov (United States)

    ... for MDA Blog Donate Search MDA.org Close Charcot-Marie-Tooth Disease (CMT) Share print email share facebook twitter ... disrupt these interactions. The many different types of Charcot-Marie-Tooth (CMT) are distinguished by age of onset, inheritance ...

  4. Contract types - turnkey

    International Nuclear Information System (INIS)

    Loeffler, G.

    1975-01-01

    Turnkey or the turnkey type of contract refers to a system of management according to which one organization accepts total responsibility for completing all parts and all phases of a project. In the case of a power project the turnkey contractor undertakes to design the plant, supply or procure and erect the equipment, build the station and put it into operation. (orig./FW) [de

  5. Type 1 autoimmune pancreatitis.

    Science.gov (United States)

    Zen, Yoh; Bogdanos, Dimitrios P; Kawa, Shigeyuki

    2011-12-07

    Before the concept of autoimmune pancreatitis (AIP) was established, this form of pancreatitis had been recognized as lymphoplasmacytic sclerosing pancreatitis or non-alcoholic duct destructive chronic pancreatitis based on unique histological features. With the discovery in 2001 that serum IgG4 concentrations are specifically elevated in AIP patients, this emerging entity has been more widely accepted. Classical cases of AIP are now called type 1 as another distinct subtype (type 2 AIP) has been identified. Type 1 AIP, which accounts for 2% of chronic pancreatitis cases, predominantly affects adult males. Patients usually present with obstructive jaundice due to enlargement of the pancreatic head or thickening of the lower bile duct wall. Pancreatic cancer is the leading differential diagnosis for which serological, imaging, and histological examinations need to be considered. Serologically, an elevated level of IgG4 is the most sensitive and specific finding. Imaging features include irregular narrowing of the pancreatic duct, diffuse or focal enlargement of the pancreas, a peri-pancreatic capsule-like rim, and enhancement at the late phase of contrast-enhanced images. Biopsy or surgical specimens show diffuse lymphoplasmacytic infiltration containing many IgG4+ plasma cells, storiform fibrosis, and obliterative phlebitis. A dramatic response to steroid therapy is another characteristic, and serological or radiological effects are normally identified within the first 2 or 3 weeks. Type 1 AIP is estimated as a pancreatic manifestation of systemic IgG4-related disease based on the fact that synchronous or metachronous lesions can develop in multiple organs (e.g. bile duct, salivary/lacrimal glands, retroperitoneum, artery, lung, and kidney) and those lesions are histologically identical irrespective of the organ of origin. Several potential autoantigens have been identified so far. A Th2-dominant immune reaction and the activation of regulatory T-cells are assumed

  6. Type 1 autoimmune pancreatitis

    Directory of Open Access Journals (Sweden)

    Zen Yoh

    2011-12-01

    Full Text Available Abstract Before the concept of autoimmune pancreatitis (AIP was established, this form of pancreatitis had been recognized as lymphoplasmacytic sclerosing pancreatitis or non-alcoholic duct destructive chronic pancreatitis based on unique histological features. With the discovery in 2001 that serum IgG4 concentrations are specifically elevated in AIP patients, this emerging entity has been more widely accepted. Classical cases of AIP are now called type 1 as another distinct subtype (type 2 AIP has been identified. Type 1 AIP, which accounts for 2% of chronic pancreatitis cases, predominantly affects adult males. Patients usually present with obstructive jaundice due to enlargement of the pancreatic head or thickening of the lower bile duct wall. Pancreatic cancer is the leading differential diagnosis for which serological, imaging, and histological examinations need to be considered. Serologically, an elevated level of IgG4 is the most sensitive and specific finding. Imaging features include irregular narrowing of the pancreatic duct, diffuse or focal enlargement of the pancreas, a peri-pancreatic capsule-like rim, and enhancement at the late phase of contrast-enhanced images. Biopsy or surgical specimens show diffuse lymphoplasmacytic infiltration containing many IgG4+ plasma cells, storiform fibrosis, and obliterative phlebitis. A dramatic response to steroid therapy is another characteristic, and serological or radiological effects are normally identified within the first 2 or 3 weeks. Type 1 AIP is estimated as a pancreatic manifestation of systemic IgG4-related disease based on the fact that synchronous or metachronous lesions can develop in multiple organs (e.g. bile duct, salivary/lacrimal glands, retroperitoneum, artery, lung, and kidney and those lesions are histologically identical irrespective of the organ of origin. Several potential autoantigens have been identified so far. A Th2-dominant immune reaction and the activation of

  7. Tension-type headache

    DEFF Research Database (Denmark)

    Bendtsen, Lars; Jensen, Rigmor; Bendtsen, Lars

    2009-01-01

    The substantial societal and individual burdens associated with tension-type headache (TTH) constitute a previously overlooked major public health issue. TTH is prevalent, affecting up to 78% of the general population, and 3% suffer from chronic TTH. Pericranial myofascial nociception probably...... is important for the pathophysiology of episodic TTH, whereas sensitization of central nociceptive pathways seems responsible for the conversion of episodic to chronic TTH. Headache-related disability usually can be reduced by identification of trigger factors combined with nonpharmacologic and pharmacologic...

  8. Variations of interferometer types

    International Nuclear Information System (INIS)

    Graeff, W.

    1978-01-01

    The search for other interferometer configurations than the LLL interferometer that has been proved to work satisfactorily, has two reasons: first some disadvantages of the LLL interferometer like the smearins of the beams over the Borrmann fan or the loss of half of the intensity in the Laue case mirror may be overcome by changing the geometry. Secondly, problems of neutron optics like details of wave propagation in perfect and nearly perfect crystals coherence etc. can be investigated by varying the properties of the interferometer components. The discussion is restricted to those inteferometer types where Bragg diffracting single crystals are used for beam handling

  9. Type 2 diabetes mellitus

    DEFF Research Database (Denmark)

    DeFronzo, Ralph A; Ferrannini, Ele; Groop, Leif

    2015-01-01

    Type 2 diabetes mellitus (T2DM) is an expanding global health problem, closely linked to the epidemic of obesity. Individuals with T2DM are at high risk for both microvascular complications (including retinopathy, nephropathy and neuropathy) and macrovascular complications (such as cardiovascular...... that multiple antidiabetic agents, used in combination, will be required to maintain normoglycaemia. The treatment must not only be effective and safe but also improve the quality of life. Several novel medications are in development, but the greatest need is for agents that enhance insulin sensitivity, halt...

  10. Representing Session Types

    DEFF Research Database (Denmark)

    Bock, Peter Brottveit; Murawska, Agata; Bruni, Alessandro

    2016-01-01

    In this paper we propose a logical foundation of processes and their focused normal forms. We use a linear meta-language based on substructural operational semantics to describe focused forms of processes, and compare them to standard π-calculus processes with their respective operational semantics....... The overall goal of this research is to understand how to reason about processes, multiparty communication and global types, and how to mechanize properties such as deadlock freeness and liveness. We are also interested in establishing the limitations of this approach....

  11. Type 1 narcolepsy

    DEFF Research Database (Denmark)

    Degn, Matilda; Kornum, Birgitte Rahbek

    2015-01-01

    Type 1 narcolepsy is a sleep disorder characterized by excessive daytime sleepiness with unintentional sleep attacks and cataplexy. The disorder is caused by a loss of hypocretinergic neurons in the brain. The specific loss of these neurons in narcolepsy is thought to result from an autoimmune...... attack, and this is supported by evidence of both environmental and genetic factors pointing toward an involvement of the immune system. However, definitive proof of an autoimmune etiology is still missing. Several different immune-mediated disorders targeting neurons are known, and many...

  12. Extending record typing to type parametric modules with sharing

    OpenAIRE

    Aponte , Maria Virginia

    1993-01-01

    Projet FORMEL; We extend term unification techniques used to type extensible records in order to solve the two main typing problems for modules in Standard ML : matching and sharing. We obtain a type system for modules based only on well known unification problems, modulo some equational theories we define. Our formalization is simple and has the elegance of polymorphic type disciplines based on unification. It can be seen as a synthesis of previous work on module and record typing.

  13. Desmoid-type fibromatosis

    International Nuclear Information System (INIS)

    Otero, S.; Moskovic, E.C.; Strauss, D.C.; Benson, C.; Miah, A.B.; Thway, K.; Messiou, C.

    2015-01-01

    Desmoid-type fibromatosis is a rare, locally infiltrative, mesenchymal neoplasm that is associated with high rates of local recurrence but lacks the potential to metastasise. The disease affects younger individuals, with a peak age of 30 years, and is the most common cause of an anterior abdominal wall mass in young women of childbearing age. It may, however, involve nearly every body part, including the extremities, head and neck, trunk, and abdominal cavity; as such, desmoid-type fibromatosis may present to a range of general and subspecialty radiologists. These rare tumours have a widely variable clinical presentation and unpredictable natural history, hence input from a soft-tissue tumour centre is recommended, although much of the imaging may be performed at the patient's local hospital. The consensus for treatment has changed over the past decade, with most centres moving away from primary radical surgery towards a front-line ‘watch-and-wait’ policy. Therefore, imaging has an increasingly important role to play in both the diagnosis and follow-up of these patients. This review will discuss the typical imaging characteristics of these lesions and suggest diagnostic and follow-up magnetic resonance imaging protocols, with details of suitable sequences and scanning intervals

  14. Stack semantics of type theory

    DEFF Research Database (Denmark)

    Coquand, Thierry; Mannaa, Bassel; Ruch, Fabian

    2017-01-01

    We give a model of dependent type theory with one univalent universe and propositional truncation interpreting a type as a stack, generalizing the groupoid model of type theory. As an application, we show that countable choice cannot be proved in dependent type theory with one univalent universe...

  15. Efficient Type Representation in TAL

    Science.gov (United States)

    Chen, Juan

    2009-01-01

    Certifying compilers generate proofs for low-level code that guarantee safety properties of the code. Type information is an essential part of safety proofs. But the size of type information remains a concern for certifying compilers in practice. This paper demonstrates type representation techniques in a large-scale compiler that achieves both concise type information and efficient type checking. In our 200,000-line certifying compiler, the size of type information is about 36% of the size of pure code and data for our benchmarks, the best result to the best of our knowledge. The type checking time is about 2% of the compilation time.

  16. Glutaric aciduria type I

    International Nuclear Information System (INIS)

    Mandel, H.; Berant, M.; Braun, J.; Technion-Israel Inst. of Tech., Haifa; El-Peleg, O.; Christensen, E.

    1991-01-01

    Serial CT findings in an infant with glutaric aciduria type I (GA-I) are reported. The major CT features were dilatation of the insular cisterns, regression of the temporal lobes, with 'bat wings' dilatation of the Sylvian fissures and hypodensity of the lenticular nuclei. CT changes preceded the onset of symptoms by 3 months. An improvement in the temporal lobe atrophy was seen after a period of treatment, coinciding with marked clinical improvement. A peculiar feature was the presence of external hydrocephalus, which diverted the attention from manifestations of the primary disease and thus constituted a diagnostic pitfall. The delineation and recognition of the characteristic radiologic manifestations of GA-I are essential for allowing an adequate radiologist/clinician interaction in diagnosing this inborn error of metabolism. (orig.)

  17. Enteroendocrine cell types revisited

    DEFF Research Database (Denmark)

    Engelstoft, Maja S; Egerod, Kristoffer Lihme; Lund, Mari L

    2013-01-01

    The GI-tract is profoundly involved in the control of metabolism through peptide hormones secreted from enteroendocrine cells scattered throughout the gut mucosa. A large number of recently generated transgenic reporter mice have allowed for direct characterization of biochemical and cell...... biological properties of these previously highly elusive enteroendocrine cells. In particular the surprisingly broad co-expression of six functionally related hormones in the intestinal enteroendocrine cells indicates that it should be possible to control not only the hormone secretion but also the type...... and number of enteroendocrine cells. However, this will require a more deep understanding of the factors controlling differentiation, gene expression and specification of the enteroendocrine cells during their weekly renewal from progenitor cells in the crypts of the mucosa....

  18. Type 1 Tyrosinaemia

    LENUS (Irish Health Repository)

    Mannion, MA

    2016-06-01

    Tyrosinaemia type 1 (TYR1, OMIM# 276700) is a rare autosomal recessive disease that results from an enzyme defect that leads to a deficiency in fumarylacetoacetase (FAH)1. We present 3 cases of TYR1 in the Irish population over a 9 year period, the only cases known to have been diagnosed in Ireland since 1989. The common presenting symptom was hypoglycaemia and the diagnosis was made by the identification of the pathognomonic biomarker succinylacetone on urine organic acid analysis. We discuss the clinical presentation, biochemical and genetic results including one novel mutation. We also highlight the importance of early initiation of Nitisinone (NTBC), which reduces the complications of TYR1 and the incidence of liver transplantation in this population2.

  19. Mechanoluminescent Contact Type Sensor

    Directory of Open Access Journals (Sweden)

    A. K. Yefremov

    2017-01-01

    Full Text Available Mechanoluminescent sensing elements convert mechanical stress into optical radiation. Advantages of such sensors are the ability to generate an optical signal, solid-state, simple structure, and resistance to electromagnetic interference. Mechanoluminescent sensor implementations can possess the concentrated and distributed sensitivity, thereby allowing us to detect the field of mechanical stresses distributed across the area and in volume. Most modern semiconductor photo-detectors can detect mechanoluminescent radiation, so there are no difficulties to provide its detection when designing the mechanoluminescent sensing devices. Mechanoluminescent substances have especial sensitivity to shock loads, and this effect can be used to create a fuse the structure of which includes a target contact type sensor with a photosensitive actuator. The paper briefly describes the theoretical basics of mechanoluminiscence: a light signal emerges from the interaction of crystalline phosphor luminescence centers with electrically charged dislocations, moving due to the deformation of the crystal. A mathematical model of the mechanoluminescent conversion is represented as a functional interaction between parameters of the mechanical shock excitation and the sensor light emission. Examples of computing the optical mechanoluminescent output signal depending on the duration and peak level of impulse load are given. It is shown that the luminous flux, generated by mechanoluminescent sensing element when there is an ammunition-target collision causes the current emerging in photo-detector (photodiode that is sufficient for a typical actuator of the fuse train to operate. The potential possibility to create a contact target type sensor based on the light-sensitive mechanoluminescent sensor was proved by the calculation and simulation results.

  20. EXPERIMENTAL PNEUMONIA (FRIEDLANDER TYPE).

    Science.gov (United States)

    Sisson, W R; Walker, I C

    1915-12-01

    The foregoing experiments show that in cats a definite lobar pneumonia may be caused by Bacillus mucosus capsulatus. Judging both from the clinical course and from the pathological findings, this form of pulmonary infection differs from the usual pneumococcus types of pneumonia and closely resembles the so called Friedländer's bacillus or Bacillus pneumonioe in man. In all instances in which a lobar pneumonia was found after the injection of the bacillus, a similar organism was recovered from the lung, and in no case was this associated with other organisms. The course of the disease in cats is very short, the animals developing early symptoms of profound toxemia. In 87 per cent of the animals showing a lobar pneumonia positive blood cultures were obtained. The pathological findings, judging from the early stages of the disease, are subject to considerable variation. In some instances the process may suggest a pseudolobar or confluent lobular distribution. In these cases the lung has a mottled, marble-like appearance. In the majority of cases, however, the process gave a more homogeneous appearance, suggesting a diffuse and uniform distribution. Foci of hemorrhage were not uncommon in both. Such areas cause the mottled appearance sometimes found. In all instances the consolidated lung presents a greater infiltration of tissue than is usually seen in other types of experimental pneumonia. Although the exudate as seen on the cut surface may be abundant and especially viscid in character, this is not present in most cases. The cut surface of the consolidated lung does not present a granular appearance. The histological findings are also subject to considerable variation. In most instances the infundibular and alveolar spaces are completely filled with an exudate made up chiefly of polymorphonuclear cells. Associated with these are the capsulated bacilli, large vacuolated mononuclear phagocytic cells, and red blood cells, and occasionally small amounts of fibrin. The

  1. Object-Oriented Type Systems

    DEFF Research Database (Denmark)

    Schwartzbach, Michael Ignatieff; Palsberg, Jens

    binding. Existing languages employ different type systems, and it can be difficult to compare, evaluate and improve them, since there is currently no uniform theory for such languages. This book provides such a theory. The authors review the type systems of Simula, Smalltalk, C++ and Eiffel and present......Object-Oriented Type Systems Jens Palsberg and Michael I. Schwartzbach Aarhus University, Denmark Type systems are required to ensure reliability and efficiency of software. For object-oriented languages, typing is an especially challenging problem because of inheritance, assignment, and late...... a type system that generalizes and explains them. The theory is based on an idealized object-oriented language called BOPL (Basic Object Programming Language), containing common features of the above languages. A type system, type inference algorithm, and typings of inheritance and genericity...

  2. Pediatric obesity & type 2 diabetes.

    Science.gov (United States)

    Dea, Tara L

    2011-01-01

    This article focuses on (a) identifying obesity and other risk factors for developing type 2 diabetes, (b) differentiating between pediatric type 1 diabetes and type 2 diabetes, and (c) treating pediatric type 2 diabetes. Obesity has significant implications on a child's health, including an increased risk for insulin resistance and progression to type 2 diabetes. Type 2 diabetes in children, characterized by insulin resistance and relative pancreatic b-cell failure due to the increased demand for insulin production, has now reached epidemic proportions. Longitudinal research on pediatric type 2 diabetes, however, is lacking because this epidemic is relatively new. Treatment of type 2 diabetes in children is focused on lifestyle modification with weight management/increased physical activity, and pharmacological management through oral medication or insulin therapy. Because children with type 2 diabetes are at risk for developing diabetes-related complications earlier in life, they need to be closely monitored for comorbidities.

  3. Object-Oriented Type Systems

    DEFF Research Database (Denmark)

    Schwartzbach, Michael Ignatieff; Palsberg, Jens

    a type system that generalizes and explains them. The theory is based on an idealized object-oriented language called BOPL (Basic Object Programming Language), containing common features of the above languages. A type system, type inference algorithm, and typings of inheritance and genericity...... binding. Existing languages employ different type systems, and it can be difficult to compare, evaluate and improve them, since there is currently no uniform theory for such languages. This book provides such a theory. The authors review the type systems of Simula, Smalltalk, C++ and Eiffel and present......Object-Oriented Type Systems Jens Palsberg and Michael I. Schwartzbach Aarhus University, Denmark Type systems are required to ensure reliability and efficiency of software. For object-oriented languages, typing is an especially challenging problem because of inheritance, assignment, and late...

  4. Presenting symptoms in type 1 vs. type 2 myocardial infarction

    DEFF Research Database (Denmark)

    Saaby, L.; Sarkisian, Laura; Poulsen, T. S.

    2015-01-01

    Introduction: The classification of myocardial infarction (MI) into five types was introduced in 2007 as a component of the Universal definition. However, data outlining clinical symptoms in different MI types are limited. Purpose: To describe the presenting symptoms in patients with type 1 MI vs...... on the debut symptoms at the time of MI. The diagnosis and classification of MI were according to the Universal definition. Thus, a rise/fall pattern of troponin values was required with at least one value above the 99th percentile of the upper reference limit. Also, clilinical evidence of myocardial ischemia...... had to be present. Results: During the inclusion period 360 patients with a type 1 MI were indentified, whereas 119 patients had a type 2 MI. As shown in the Table patients with type 1 MI more frequently had chest pain/discomfort than type 2 MI patients. However, patients with type 2 MI more often...

  5. A dependently-typed construction of semi-simplicial types

    OpenAIRE

    Herbelin, Hugo

    2015-01-01

    International audience; This paper presents a dependently-typed construction of semi-simplicial sets in type theory where sets are taken to be types. This addresses an open question raised on the wiki of the special year on Univalent Foundations at the Institute of Advanced Study (2012-2013).

  6. LMFBR type reactor

    International Nuclear Information System (INIS)

    Kumaoka, Yoshio; Kawamura, Yutaka.

    1990-01-01

    A main vessel support skirt is supported by a base mat of reactor buildings and the base mat is supported by means of an earthquake-proof device on concretes of a lower raft disposed on ground rocks. The earthquake-proof device is constituted by alternately stacking, laminating and press-bonding thin steel plates together with thin rubber layers between an upper flange and a lower raft. Thus, for the horizontal seismic vibrations, the period of the swinging in the horizontal direction of the buildings is made greater than the swinging period of earthquakes by the earthquake-proof device to reduce the impact shocks of earthquakes. Further, for the vertical seismic vibrations, the input seismic movements are not amplified during transmission from the base mat of the buildings to the reactor structure by way of the support skirt of the main vessel, due to the shortened load transmission path and the seismic power design to the reactor structure can be moderated sufficiently. A safety LMFBR type reactor with reduced construction cost and improved reliability can be attained. (N.H.)

  7. Miniaturized stirling type cooler

    International Nuclear Information System (INIS)

    Pundak, N.

    1988-01-01

    This patent describes a cryogenic Stirling type cooler system, an axially extending casing, a compressor unit located within the casing and including a crankshaft extending transversely of the casing axis, an expander and expander connecting rod arranged co-axially in and with the casing the casing including a cover having an axis in coaxial relation with the crankshaft, the casing and cover forming a sealed housing for the compressor unit and crankshaft. The cover consists of a cup-shaped non-magnetic partition, a drive for the compressor unit comprising a D.C. brushless motor including a stator, a rotor and driving electronics. The rotor located within the cover in the sealed housing and coupled directly to the crankshaft, the crankshaft connected to the expander and compressor connecting rods, the stator located outwardly of an encircling the cover in co-axial relation with the rotor. The drive electronics located outwardly of the casing, whereby the rotor is located within the sealed housing in driving engagement with the crankshaft while the stator is located outside the sealed housing for driving the rotor so that the rotor supplies rotational movement to the crankshaft which is converted by the crankshaft cam for driving the expander and compressor connecting rod

  8. FBR type reactor

    International Nuclear Information System (INIS)

    Kimura, Kimitaka; Fukuie, Ken; Iijima, Tooru; Shimpo, Masakazu.

    1994-01-01

    In an FBR type reactor for exchanging fuels by pulling up reactor core upper mechanisms, a connection mechanism is disposed for connecting the top of the reactor core and the lower end of the reactor core upper mechanisms. In addition, a cylindrical body is disposed surrounding the reactor core upper mechanisms, and a support member is disposed to the cylindrical body for supporting an intermediate portion of the reactor core upper mechanisms. Then, the lower end of the reactor core upper mechanisms is connected to the top of the reactor core. Same displacements are caused to both of them upon occurrence of earthquakes and, as a result, it is possible to eliminate mutual horizontal displacement between a control rod guide hole of the reactor core upper mechanisms and a control rod insertion hole of the reactor core. In addition, since the intermediate portion of the reactor core upper mechanisms is supported by the support member disposed to the cylindrical body surrounding the reactor core upper mechanisms, deformation caused to the lower end of the reactor core upper mechanisms is reduced, so that the mutual horizontal displacement with respect to the control rod insertion hole of the reactor core can be reduced. As a result, performance of control rod insertion upon occurrence of the earthquakes is improved, so that reactor shutdown is conducted more reliably to improve reactor safety. (N.H.)

  9. BWR type reactor core

    International Nuclear Information System (INIS)

    Tatemichi, Shin-ichiro.

    1981-01-01

    Purpose: To eliminate the variation in the power distribution of a BWR type reactor core in the axial direction even if the flow rate is increased or decreased by providing a difference in the void coefficient between the upper part and the lower parts of the reactor core, and increasing the void coefficient at the lower part of the reactor core. Constitution: The void coefficient of the lower region from the center to the lower part along the axial direction of a nuclear fuel assembly is increased to decrease the dependence on the flow rate of the axial power distribution of the nuclear fuel assembly. That is, a water/fuel ratio is varied, the water in non-boiled region is increased or the neutron spectrum is varied so as to vary the void coefficient. In order to exemplify it, the rate of the internal pellets of the fuel rod of the nuclear fuel assembly or the shape of the channel box is varied. Accordingly, the power does not considerably vary even if the flow rate is altered since the power is varied in the power operation. (Yoshihara, H.)

  10. Manipulator type book

    International Nuclear Information System (INIS)

    Koehler, G.W.

    1981-01-01

    Manipulators and similar equipment operated by personnel constitute one of the two major branches of handling technology besides program controlled units (industrial robots and feeding machines). Despite the widespread use of remote handling equipment in nuclear engineering, its growing importance and increasing application also in other areas, a comprehensive treatment of the field has so far been missing. This gap is now filled with the manipulator type book. The bulk of the volume is reserved to remote handling equipment for nuclear purposes available in the international market. However, the survey would be incomplete, also for potential interactions, without manipulators now used also for purposes other than nuclear technology, and without a reference to experimental units and developments which may be assumed to reach practical application one day. This book has been written to help all those who are involved in remote handling technology in one way or the other - plant designers, public authorities and users of such equipment. The text is printed both in German and English for the benefit of foreign readers. A standardized language is proposed to improve communication. (orig./HP) [de

  11. LMFBR type reactor

    International Nuclear Information System (INIS)

    Masumi, Ryoji; Kawashima, Katsuyuki; Kurihara, Kunitoshi.

    1988-01-01

    Purpose: To flatten the power distribution while maintaining the flattening in the axial power distribution in LMFBR type reactors. Constitution: Main system control rods are divided into control rods used for the operation and starting rods used for the starting of the reactor, and the starting rods are disposed in the radial periphery of the reactor core, while the control rods are disposed to the inside of the starting rods. With such a constitution, adjusting rods can be disposed in the region where the radial power peaking is generated to facilitate the flattening of the power distribution even in such a design that the ratio of the number of control rods to that of fuel assemblies is relatively large. That is, in this reactor, the radial power peaking is reduced by about 10% as compared with the conventional reactor core. As a result, the maximum linear power density during operation is reduced by about 10% to increase the thermal margin of the reactor core. If the maximum linear power density is set identical, the number of the fuel assemblies can be decreased by about 10%, to thereby reduce the fuel production cost. (K.M.)

  12. Tornado type wind turbines

    Science.gov (United States)

    Hsu, Cheng-Ting

    1984-01-01

    A tornado type wind turbine has a vertically disposed wind collecting tower with spaced apart inner and outer walls and a central bore. The upper end of the tower is open while the lower end of the structure is in communication with a wind intake chamber. An opening in the wind chamber is positioned over a turbine which is in driving communication with an electrical generator. An opening between the inner and outer walls at the lower end of the tower permits radially flowing air to enter the space between the inner and outer walls while a vertically disposed opening in the wind collecting tower permits tangentially flowing air to enter the central bore. A porous portion of the inner wall permits the radially flowing air to interact with the tangentially flowing air so as to create an intensified vortex flow which exits out of the top opening of the tower so as to create a low pressure core and thus draw air through the opening of the wind intake chamber so as to drive the turbine.

  13. Play the Blood Typing Game

    Science.gov (United States)

    ... a desire to learn how one determines blood types, their differences and which ones are compatible for blood transfusions. ” See a Video about the Blood Typing Game 3 min. Play 1. ploster 3480 2. Yokota ...

  14. Treatise on intuitionistic type theory

    CERN Document Server

    Granström, Johan Georg

    2011-01-01

    Intuitionistic type theory can be described, somewhat boldly, as a fulfillment of the dream of a universal language for science.  In particular, intuitionistic type theory is a foundation for mathematics and a programming language.

  15. Types of Cancer Teens Get

    Science.gov (United States)

    ... Feelings Expert Answers Q&A Movies & More for Teens Teens site Sitio para adolescentes Body Mind Sexual ... for Educators Search English Español Types of Cancer Teens Get KidsHealth / For Teens / Types of Cancer Teens ...

  16. Pneumococcal Disease: Types of Infection

    Science.gov (United States)

    ... World Health Organization National Foundation for Infectious Diseases Sepsis Types of Infection Recommend on Facebook Tweet Share Compartir Streptococcus pneumoniae bacteria, or pneumococcus, can cause many types of illnesses. Some of these illnesses ...

  17. Computing effects for correspondence types

    OpenAIRE

    Hüttel, Hans

    2010-01-01

    We show that type and effect inference is possible for a type and  effect system for authenticity using non-injective correspondences, opponent  types and a spi-calculus with symmetric encryption. We do this by a general  account of how effects can be computed given knowledge of how and where they  appear in type judgments. 

  18. Lectin typing of Campylobacter concisus

    DEFF Research Database (Denmark)

    Aabenhus, Rune Munck; Hynes, Sean O; Permin, Henrik

    2002-01-01

    A total of 44 clinical isolates and the type strain of the putative pathogen Campylobacter concisus were grouped based on their reactions with plant lectins. The optimized lectin typing system used C. concisus strains proteolytically pretreated and subsequently typed by using a panel of four...... lectins. The system grouped all 45 strains into 13 lectin reaction patterns, leaving no strain untypeable due to autoagglutination. Lectin types were both stable and reproducible....

  19. Dynamic Typing: Syntax and Proof Theory

    DEFF Research Database (Denmark)

    Henglein, Fritz

    1994-01-01

    Dynamic typing, coercions, dynamically typed lambda-calculus, type inference coherence, completions, safety, minimality......Dynamic typing, coercions, dynamically typed lambda-calculus, type inference coherence, completions, safety, minimality...

  20. Exploring legacy systems using types

    NARCIS (Netherlands)

    A. van Deursen (Arie); L.M.F. Moonen (Leon)

    2000-01-01

    textabstractWe show how hypertext-based program understanding tools can achieve new levels of abstraction by using inferred type information for cases where the subject software system is written in a weakly typed language. We propose TypeExplorer, a tool for browsing COBOL legacy systems based on

  1. Case 22:Type II diabetes

    Science.gov (United States)

    Diabetes mellitus is characterized by elevated blood glucose levels. It is composed of two types depending on the pathogenesis. Type I diabetes is characterized by insulin deficiency and usually has its onset during childhood or teenage years. This is also called ketosis-prone diabetes. Type II diab...

  2. Lectin typing of Campylobacter concisus

    DEFF Research Database (Denmark)

    Aabenhus, Rune Munck; Hynes, Sean O; Permin, Henrik

    2002-01-01

    A total of 44 clinical isolates and the type strain of the putative pathogen Campylobacter concisus were grouped based on their reactions with plant lectins. The optimized lectin typing system used C. concisus strains proteolytically pretreated and subsequently typed by using a panel of four...

  3. Computing effects for correspondence types

    DEFF Research Database (Denmark)

    Hüttel, Hans

    2010-01-01

    We show that type and effect inference is possible for a type and  effect system for authenticity using non-injective correspondences, opponent  types and a spi-calculus with symmetric encryption. We do this by a general  account of how effects can be computed given knowledge of how and where they...

  4. Magnetoelastic Generator Type Transducer

    Directory of Open Access Journals (Sweden)

    A. K. Efremov

    2014-01-01

    Full Text Available Some issues relating to usage of magnetoelectric generator type transducers as the means of measuring intense dynamic loads and as a sensitive element of fuse contact target sensor (CTS are considered. Particular attention is paid to the magnetoanisotropic transducer (MAT, the principle of operation of which is based on the change of the magnetic field form caused by the applied mechanical load leading to the appearance of EMF in the output winding. The MAT, especially monolithic, has such advantages as high strength, reliability, endurance and design simplicity.The functional transducer schemes have been analyzed and for the first time it was shown that there is a possibility of using a version with only one output winding arranged in the magnetic conductor made of magnetically soft material such as structural steel. A mathematical model of transducer is proposed showing that the input signal formed by the external load is proportional to its derivative. With a sufficiently large time constant of the electric circuit and the implementation of a number of additional conditions the transducer may function as an integrator. By that it becomes possible to measure the parameters of dynamic processes having the duration of a few to tens of microseconds. Unlike the traditional transducers such as piezoelectric the output signal is not “masked” by the natural oscillations.The mechanism of the generator effect was considered leading to the “piezomagnetodynamic” model, which includes a number of phenomenological parameters. Some corresponding experimentally derived hysteresis curves are presented. Their vertical shift quantifies the generator effect and does not depend on the intensity of the magnetic field.As an example of practical application of the MAT some results of evaluation of the dynamic force characteristic of the heading part of a piezoelectric fuse are presented. The MAT was also used for the evaluation of back effects of the bullet

  5. TypePad For Dummies

    CERN Document Server

    Nelson, Melanie

    2010-01-01

    TypePad for Dummies will be on guiding readers through the technical tasks necessary for starting, using and customizing a TypePad blog. It will comprehensively explain choosing the right TypePad membership plan, singing up, configuring, using and customizing a blog using the TypePad system. It will also include: Illustrations from real-world blogs with screenshots and specific examples that bring the book's concepts and ideas to life.; Step-by-step tutorials that will walk readers through the process of signing up for a new TypePad blog and getting down the business of publishing their conten

  6. Hand functions in type 1 and type 2 diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Akpinar Pinar

    2017-01-01

    Full Text Available Introduction/Objective. Hand functions have an enormous impact on activities of daily living in patients with diabetes mellitus (DM, such as self-care, administering insulin injections, and preparing and eating meals. The aim of the study was to evaluate hand functions and grip strength in patients with type 1 and type 2 DM. Methods. This was an observational case-control study investigating the hand functions and grip strength in patients with type 1 and type 2 DM. The study comprised 41 patients with type 1 DM aged 25–50 years sex- and age-matched, 40 non-diabetic controls, and 91 patients with type 2 DM aged 40–65 years sex- and age-matched 60 non-diabetic controls. Patients with documented history of diabetic sensorimotor neuropathy and adhesive capsulitis were excluded. The Duruoz Hand Index was used to assess the functional hand disability. Grip strength was tested with a calibrated Jamar dynamometer. Results. The Duruoz Hand Index scores in patients with type 2 DM were significantly higher than in persons in the control group (p 0.05. Grip strength values of patients with type 1 DM were significantly lower compared to those in the control group (p < 0.05, whereas there was no significant difference between patients with type 2 DM and their control group. There was a negatively significant correlation between grip strength and the Duruoz Hand Index scores in patients with both type 1 and type 2 DM (p < 0.05. Conclusion. Patients with type 1 DM and type 2 DM have different degrees of hand disability as compared to healthy control groups.

  7. Composing and decomposing data types

    DEFF Research Database (Denmark)

    Bahr, Patrick

    2014-01-01

    Wouter Swierstra's data types à la carte is a technique to modularise data type definitions in Haskell. We give an alternative implementation of data types à la carte that offers more flexibility in composing and decomposing data types. To achieve this, we refine the subtyping constraint, which...... is at the centre of data types à la carte. On the one hand this refinement is more general, allowing subtypings that intuitively should hold but were not derivable beforehand. This aspect of our implementation removes previous restrictions on how data types can be combined. On the other hand our refinement is more...... restrictive, disallowing subtypings that lead to more than one possible injection and should therefore be considered programming errors. Furthermore, from this refined subtyping constraint we derive a new constraint to express type isomorphism. We show how this isomorphism constraint allows us to decompose...

  8. Type-2 fuzzy sets: geometric defuzzification and type-reduction

    OpenAIRE

    Coupland, Simon

    2007-01-01

    This paper presents the geometric defuzzifier for general type-2 fuzzy sets. This novel method has the potential to transform the fuzzy control paradigm. General type-2 fuzzy logic is better able to model noise and uncertainty but suffers from the massive computational cost of defuzzification. This paper uses geometry to eliminate this problem, paving the way for general type-2 fuzzy control. This paper was shortlisted for the best paper award at this prestigious international conference.

  9. Typing is writing: Linguistic properties modulate typing execution.

    Science.gov (United States)

    Pinet, Svetlana; Ziegler, Johannes C; Alario, F-Xavier

    2016-12-01

    Typing is becoming our preferred way of writing. Perhaps because of the relative recency of this change, very few studies have investigated typing from a psycholinguistic perspective. In addition, and despite obvious similarities between typing and handwriting, typing research has remained rather disconnected from handwriting research. The current study aimed at bridging this gap by evaluating how typing is affected by a number of psycholinguistic variables defined at the word, syllable, and letter levels. In a writing-to-dictation task, we assessed typing performance by measuring response accuracy, onset latencies - an index of response preparation and initiation - and interkeystroke intervals (IKIs) - an index of response execution processes. The lexical and sublexical factors revealed a composite pattern of effects. Lexical frequency improved response latencies and accuracy, while bigram frequency speeded up IKIs. Sound-spelling consistency improved latencies, but had an inhibitory effect on IKI. IKIs were also longer at syllable boundaries. Together, our findings can be fit within a framework for typed production that combines the previously developed theories of spelling and typing execution. At their interface, we highlight the need for an intermediate hierarchical stage, perhaps in the form of a graphemic buffer for typing.

  10. Early onset type 2 diabetes

    DEFF Research Database (Denmark)

    Bo, A; Thomsen, R W; Nielsen, J S

    2018-01-01

    AIM: To examine the association between early onset of type 2 diabetes (DM) and clinical and behavioural risk factors for later diabetes complications. METHODS: We conducted a cross-sectional study of 5115 persons with incident type 2 DM enrolled during 2010-2015 in the Danish Centre for Strategic...... Research in Type 2 Diabetes-cohort. We compared risk factors at time of diagnosis among those diagnosed at ≤45 years (early-onset) with diagnosis age 46-55, 56-65 (average-onset = reference), 66-75, and >75 years (late-onset). Prevalence ratios (PRs) were computed using Poisson regression. RESULTS: Poor...... was more frequent and meeting physical activity recommendations less likely in persons with early-onset type 2 DM. CONCLUSIONS: We found a clear age-gradient, with increasing prevalence of clinical and behavioural risk factors the younger the onset age of type 2 DM. Younger persons with early-onset type 2...

  11. Object-Oriented Type Systems

    DEFF Research Database (Denmark)

    Schwartzbach, Michael Ignatieff; Palsberg, Jens

    Object-Oriented Type Systems Jens Palsberg and Michael I. Schwartzbach Aarhus University, Denmark Type systems are required to ensure reliability and efficiency of software. For object-oriented languages, typing is an especially challenging problem because of inheritance, assignment, and late...... are provided for BOPL. Throughout, the results are related to the languages on which BOPL is based. This text offers advanced undergraduates and professional software developers a sound understanding of the key aspects of object-oriented type systems. All algorithms are implemented in a freely available...... binding. Existing languages employ different type systems, and it can be difficult to compare, evaluate and improve them, since there is currently no uniform theory for such languages. This book provides such a theory. The authors review the type systems of Simula, Smalltalk, C++ and Eiffel and present...

  12. Types for DSP Assembler Programs

    DEFF Research Database (Denmark)

    Larsen, Ken

    2006-01-01

    for reuse, and a procedure that computes point-wise vector multiplication. The latter uses a common idiom of prefetching memory resulting in out-of-bounds reading from memory. I present two extensions to the baseline type system: The first extension is a simple modification of some type rules to allow out......-ofbounds reading from memory. The second extension is based on two major modifications of the baseline type system: • Abandoning the type-invariance principle of memory locations and using a variation of alias types instead. • Introducing aggregate types, making it possible to have different views of a block...... in assembler language. However, programming in assembler causes numerous problems, such as memory corruption, for instance. To test the thesis I define a model assembler language called Featherweight DSP which captures some of the essential features of a real custom DSP used in the industrial partner's digital...

  13. Types for BioAmbients

    Directory of Open Access Journals (Sweden)

    Sara Capecchi

    2010-02-01

    Full Text Available The BioAmbients calculus is a process algebra suitable for representing compartmentalization, molecular localization and movements between compartments. In this paper we enrich this calculus with a static type system classifying each ambient with group types specifying the kind of compartments in which the ambient can stay. The type system ensures that, in a well-typed process, ambients cannot be nested in a way that violates the type hierarchy. Exploiting the information given by the group types, we also extend the operational semantics of BioAmbients with rules signalling errors that may derive from undesired ambients' moves (i.e. merging incompatible tissues. Thus, the signal of errors can help the modeller to detect and locate unwanted situations that may arise in a biological system, and give practical hints on how to avoid the undesired behaviour.

  14. Behavioral types in programming languages

    OpenAIRE

    Yoshida, Nobuko; Vasconcelos, Vasco T.; Padovani, Luca; Bono, Nicholas Ng; Neykova, Rumyana; Montesi, Fabrizio; Mascardi, Viviana; Martins, Francisco; Johnsen, Einar Broch; Hu, Raymond; Giachino, Elena; Gesbert, Nils; Gay, Simon J.; Deniélou, Pierre-Malo; Castagna, Giuseppe

    2016-01-01

    A recent trend in programming language research is to use behav- ioral type theory to ensure various correctness properties of large- scale, communication-intensive systems. Behavioral types encompass concepts such as interfaces, communication protocols, contracts, and choreography. The successful application of behavioral types requires a solid understanding of several practical aspects, from their represen- tation in a concrete programming language, to their integration with other programmi...

  15. Intensional Analysis of Quantified Types

    National Research Council Canada - National Science Library

    Saha, Bratin; Trifonov, Valery; Shao, Zhong

    2005-01-01

    Compilers for polymorphic languages can use run-time type inspection to support advanced implementation techniques such as tagless garbage collection, polymorphic marshalling, and flattened data structures...

  16. Fully Reflexive Intensional Type Analysis

    National Research Council Canada - National Science Library

    Saha, Bratin; Trifonov, Valery; Shao, Zhong

    2005-01-01

    Compilers for polymorphic languages can use runtime type inspection to support advanced implementation techniques such as tagless garbage collection, polymorphic marshalling, and flattened data structures...

  17. Fungal type III polyketide synthases.

    Science.gov (United States)

    Hashimoto, Makoto; Nonaka, Takamasa; Fujii, Isao

    2014-10-01

    This article covers the literature on fungal type III polyketide synthases (PKSs) published from 2005 to 2014. Since the first discovery of fungal type III PKS genes in Aspergillus oryzae, reported in 2005, putative genes for type III PKSs have been discovered in fungal genomes. Compared with type I PKSs, type III PKSs are much less abundant in fungi. However, type III PKSs could have some critical roles in fungi. This article summarizes the studies on fungal type III PKS functional analysis, including Neurospora crassa ORAS, Aspergillus niger AnPKS, Botrytis cinerea BPKS and Aspergillus oryzae CsyA and CsyB. It is mostly in vitro analysis using their recombinant enzymes that has revealed their starter and product specificities. Of these, CsyB was found to be a new kind of type III PKS that catalyses the coupling of two β-keto fatty acyl CoAs. Homology modelling reported in this article supports the importance of the capacity of the acyl binding tunnel and active site cavity in fungal type III PKSs.

  18. A Type System for Tom

    Directory of Open Access Journals (Sweden)

    Claude Kirchner

    2010-03-01

    Full Text Available Extending a given language with new dedicated features is a general and quite used approach to make the programming language more adapted to problems. Being closer to the application, this leads to less programming flaws and easier maintenance. But of course one would still like to perform program analysis on these kinds of extended languages, in particular type checking and inference. In this case one has to make the typing of the extended features compatible with the ones in the starting language. The Tom programming language is a typical example of such a situation as it consists of an extension of Java that adds pattern matching, more particularly associative pattern matching, and reduction strategies. This paper presents a type system with subtyping for Tom, that is compatible with Java's type system, and that performs both type checking and type inference. We propose an algorithm that checks if all patterns of a Tom program are well-typed. In addition, we propose an algorithm based on equality and subtyping constraints that infers types of variables occurring in a pattern. Both algorithms are exemplified and the proposed type system is showed to be sound and complete.

  19. Object-Oriented Type Inference

    DEFF Research Database (Denmark)

    Schwartzbach, Michael Ignatieff; Palsberg, Jens

    1991-01-01

    We present a new approach to inferring types in untyped object-oriented programs with inheritance, assignments, and late binding. It guarantees that all messages are understood, annotates the program with type information, allows polymorphic methods, and can be used as the basis of an op-timizing......We present a new approach to inferring types in untyped object-oriented programs with inheritance, assignments, and late binding. It guarantees that all messages are understood, annotates the program with type information, allows polymorphic methods, and can be used as the basis of an op...

  20. Equations of the mixed type

    CERN Document Server

    Bitsadze, A V

    1963-01-01

    Equations of the Mixed Type compiles a series of lectures on certain fundamental questions in the theory of equations of mixed type. This book investigates the series of problems concerning linear partial differential equations of the second order in two variables, and possessing the property that the type of the equation changes either on the boundary of or inside the considered domain. Topics covered include general remarks on linear partial differential equations of mixed type; study of the solutions of second order hyperbolic equations with initial conditions given along the lines of parab

  1. Type-safe pattern combinators

    DEFF Research Database (Denmark)

    Rhiger, Morten

    2009-01-01

    Macros still haven't made their way into typed higher-order programming languages such as Haskell and Standard ML. Therefore, to extend the expressiveness of Haskell or Standard ML, one must express new linguistic features in terms of functions that fit within the static type systems of these lan...... of these languages. This is particularly challenging when introducing features that span across multiple types and that bind variables. We address this challenge by developing, in a step by step manner, mechanisms for encoding patterns and pattern matching in Haskell in a type-safe way....

  2. Safety Analysis versus Type Inference with Partial Types

    DEFF Research Database (Denmark)

    Schwartzbach, Michael Ignatieff; Palsberg, Jens

    1992-01-01

    perspectives, however. Safety analysis is global in that it can only analyze a complete program. In contrast, type inference is local in that it can analyze pieces of a program in isolation. In this paper we prove that safety analysis is sound, relative to both a strict and a lazy operational semantics. We......Safety analysis is an algorithm for determining if a term in an untyped lambda calculus with constants is safe, i.e., if it does not cause an error during evaluation. This ambition is also shared by algorithms for type inference. Safety analysis and type inference are based on rather different...... also prove that safety analysis accepts strictly more safe lambda terms than does type inference for simple types. The latter result demonstrates that global program analysis can be more precise than local ones....

  3. Discriminating the reaction types of plant type III polyketide synthases.

    Science.gov (United States)

    Shimizu, Yugo; Ogata, Hiroyuki; Goto, Susumu

    2017-07-01

    Functional prediction of paralogs is challenging in bioinformatics because of rapid functional diversification after gene duplication events combined with parallel acquisitions of similar functions by different paralogs. Plant type III polyketide synthases (PKSs), producing various secondary metabolites, represent a paralogous family that has undergone gene duplication and functional alteration. Currently, there is no computational method available for the functional prediction of type III PKSs. We developed a plant type III PKS reaction predictor, pPAP, based on the recently proposed classification of type III PKSs. pPAP combines two kinds of similarity measures: one calculated by profile hidden Markov models (pHMMs) built from functionally and structurally important partial sequence regions, and the other based on mutual information between residue positions. pPAP targets PKSs acting on ring-type starter substrates, and classifies their functions into four reaction types. The pHMM approach discriminated two reaction types with high accuracy (97.5%, 39/40), but its accuracy decreased when discriminating three reaction types (87.8%, 43/49). When combined with a correlation-based approach, all 49 PKSs were correctly discriminated, and pPAP was still highly accurate (91.4%, 64/70) even after adding other reaction types. These results suggest pPAP, which is based on linear discriminant analyses of similarity measures, is effective for plant type III PKS function prediction. pPAP is freely available at ftp://ftp.genome.jp/pub/tools/ppap/. goto@kuicr.kyoto-u.ac.jp. Supplementary data are available at Bioinformatics online. © The Author(s) 2017. Published by Oxford University Press.

  4. Types of subtalar joint facets.

    Science.gov (United States)

    Jung, Min-Ho; Choi, Byoung Young; Lee, Ji Yong; Han, Chang Sung; Lee, Jin Suk; Yang, Young Chul; Cho, Byung Pil

    2015-08-01

    Articular facets of the clinical subtalar joint (CSTJ) were analyzed using a total of 118 (right 57, left 61) dry, paired calcanei and tali from 68 Korean adult cadavers. The CSTJ facets were classified into the following three types depending on their continuity: type A, all three facets are separated; type B, the anterior and middle facets are partially connected; and type C, the anterior and middle facets are fused to form a single facet. The continuity between the anterior and middle facets was represented by the degree of separation (DS), which ranged between 2.00 (type A) and 1.00 (type C). Type A was most common (39.0 %) in calcanei and rarest (11.0 %) in tali. Matching of calcaneus-talus pairs yielded five combined types: A-A (11.0 %), A-B (28.0 %), B-B (18.6 %), B-C (13.6 %), and C-C (28.8 %). The mean DS was slightly greater in calcanei (1.53) than in tali (1.32), and decreased in the order of types A-A, A-B, B-B, B-C, and C-C. The intersecting angles between the anterior and middle facets, which are related to the mobility of the CSTJ, were inversely related to the DS. These findings indicate that the anterior and middle facets are fused more frequently in tali than in calcanei, and combinations of different CSTJ facet types (A-B, B-C) exist over 40 % of feet. Our results indicate that types with a smaller DS (such as B-C and C-C) are relatively mobile but less stable compared to those with a greater DS (such as A-A and A-B).

  5. Type 1 Diabetes and Sleep

    OpenAIRE

    Farabi, Sarah S.

    2016-01-01

    IN BRIEF In people with type 1 diabetes, sleep may be disrupted as a result of both behavioral and physiological aspects of diabetes and its management. This sleep disruption may negatively affect disease progression and development of complications. This review highlights key research findings regarding sleep in people with type 1 diabetes.

  6. Sandstone-type uranium deposits

    International Nuclear Information System (INIS)

    Finch, W.I.; Davis, J.F.

    1985-01-01

    World-class sandstone-type uranium deposits are defined as epigenetic concentrations of uranium minerals occurring as uneven impregnations and minor massive replacements primarily in fluvial, lacustrine, and deltaic sandstone formations. The main purpose of this introductory paper is to define, classify, and introduce to the general geologic setting for sandstone-type uranium deposits

  7. Teacher Type and Technology Training.

    Science.gov (United States)

    Rude-Parkins, Carolyn; And Others

    1993-01-01

    Discusses roles that people adopt when encountering new technology, i.e., innovators, resisters, and leaders; explains the Myers Briggs Type Indicator personality measure; and describes a study that was conducted to identify the personality types of high school teachers who participated in technology training and were successful in adopting…

  8. Types of Blood Pressure Medications

    Science.gov (United States)

    ... Peripheral Artery Disease Venous Thromboembolism Aortic Aneurysm More Types of Blood Pressure Medications Updated:Nov 6,2017 Prescription blood ... will find an overview of the classes of blood pressure medication. To expand the information on a type of medication, simply click on the subject tab. ...

  9. Bianchi type I string cosmologies

    Indian Academy of Sciences (India)

    sidered to portray early universe reasonably well. Letelier [2] obtained some particular. Bianchi type I string-dust models in which at a certain epoch, strings disappear with a phase transition to an anisotropic fluid. Another Bianchi type I model has been presented by Banerjee et al [3] which obeys Takabayashi's equation of ...

  10. Type-Directed Partial Evaluation

    DEFF Research Database (Denmark)

    Danvy, Olivier

    1998-01-01

    Type-directed partial evaluation uses a normalization function to achieve partial evaluation. These lecture notes review its background, foundations, practice, and applications. Of specific interest is the modular technique of offline and online type-directed partial evaluation in Standard ML of ...

  11. Type-Directed Partial Evaluation

    DEFF Research Database (Denmark)

    Danvy, Olivier

    1998-01-01

    Type-directed partial evaluation uses a normalization function to achieve partial evaluation. These lecture notes review its background, foundations, practice, and applications. Of specific interest is the modular technique of offline and online type-directed partial evaluation in Standard ML...

  12. Linear contextual modal type theory

    DEFF Research Database (Denmark)

    Schack-Nielsen, Anders; Schürmann, Carsten

    Abstract. When one implements a logical framework based on linear type theory, for example the Celf system [?], one is immediately con- fronted with questions about their equational theory and how to deal with logic variables. In this paper, we propose linear contextual modal type theory that gives...

  13. Type 1 Diabetes and Sleep.

    Science.gov (United States)

    Farabi, Sarah S

    2016-02-01

    IN BRIEF In people with type 1 diabetes, sleep may be disrupted as a result of both behavioral and physiological aspects of diabetes and its management. This sleep disruption may negatively affect disease progression and development of complications. This review highlights key research findings regarding sleep in people with type 1 diabetes.

  14. Completeness in Hybrid Type Theory

    DEFF Research Database (Denmark)

    Areces, Carlos; Blackburn, Patrick Rowan; Huertas, Antonia

    2014-01-01

    We show that basic hybridization (adding nominals and @ operators) makes it possible to give straightforward Henkin-style completeness proofs even when the modal logic being hybridized is higher-order. The key ideas are to add nominals as expressions of type t, and to extend to arbitrary types th...

  15. Operational Semantics of Termination Types

    DEFF Research Database (Denmark)

    Nielson, Flemming; Nielson, Hanne Riis

    1996-01-01

    and algebraic data types. The well-founded orderings are defined by pattern matching against the definition of the algebraic data types. We prove that the analysis is semantically sound with respect to a big-step (or natural) operational semantics. We compare our approach based on operational semantics to one...

  16. Personality types of oncology nurses.

    Science.gov (United States)

    Bean, C A; Holcombe, J K

    1993-12-01

    Personality type influences the choice of occupation. The breadth of specialty areas within oncology nursing allows for divergent activities and relationships and, thus, the accommodation of different personality characteristics. This exploratory study examined personality types for a convenience sample of oncology nurses predominantly employed in hospitals. According to the personality typology defined by Carl Jung, a person demonstrates a preference among four dimensions, i.e., extraversion/introversion, sensory/intuition, thinking/feeling, and judging/perceiving. The type with the strongest self-selection for these oncology nurses was ISFJ, where feeling is introverted and perception is practical, so that helping others is both a responsibility and a pleasure. The discussion relates the personality types to Jung's theory and their impact in clinical practice. Strengths and weaknesses of each personality type are described.

  17. DNA typing by capillary electrophoresis

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, N.

    1997-10-08

    Capillary electrophoresis is becoming more and more important in nucleic acid analysis including DNA sequencing, typing and disease gene measurements. This work summarized the background of DNA typing. The recent development of capillary electrophoresis was also discussed. The second part of the thesis showed the principle of DNA typing based on using the allelic ladder as the absolute standard ladder in capillary electrophoresis system. Future work will be focused on demonstrating DNA typing on multiplex loci and examples of disease diagnosis in the on-line format of PCR-CE. Also capillary array electrophoresis system should allow high throughput, fast speed DNA typing. Only the introduction and conclusions for this report are available here. A reprint was removed for separate processing.

  18. Types of hydrogenic uranium deposits

    International Nuclear Information System (INIS)

    Kondrat'eva, I.A.; Lisitsin, A.K.; Komarova, G.V.

    1980-01-01

    Principles of uranium deposit systematics are considered. Systematization, presented in this paper, is based on a regularity that the main industrial exogenic epigenetic uranium concentrations are formed in zones of reduction geochemical barriers. Types of uranium-bearing ground waters and nature of uranium reducing agents were taken into account during systematization. Hydrogenic uranium deposits are related to 3 types: formed by ground (1 type), stratal (2 type) and vein (3 type) waters. By the nature of uranium reducing agents 2 deposit subtypes are marked out: A - in rocks with syngenetic reducing agents, B - in rocks with epigenetic reducing agents. Uranium deposits are also differentiated by nature of reducing agents distribution in ore-containing rocks [ru

  19. Intersection Types and Related Systems

    Directory of Open Access Journals (Sweden)

    Paweł Parys

    2017-02-01

    Full Text Available We present a new approach to the following meta-problem: given a quantitative property of trees, design a type system such that the desired property for the tree generated by an infinitary ground lambda-term corresponds to some property of a derivation of a type for this lambda-term, in this type system. Our approach is presented in the particular case of the language finiteness problem for nondeterministic higher-order recursion schemes (HORSes: given a nondeterministic HORS, decide whether the set of all finite trees generated by this HORS is finite. We give a type system such that the HORS can generate a tree of an arbitrarily large finite size if and only if in the type system we can obtain derivations that are arbitrarily large, in an appropriate sense; the latter condition can be easily decided.

  20. Wild type measles virus attenuation independent of type I IFN

    Directory of Open Access Journals (Sweden)

    Horvat Branka

    2008-02-01

    Full Text Available Abstract Background Measles virus attenuation has been historically performed by adaptation to cell culture. The current dogma is that attenuated virus strains induce more type I IFN and are more resistant to IFN-induced protection than wild type (wt. Results The adaptation of a measles virus isolate (G954-PBL by 13 passages in Vero cells induced a strong attenuation of this strain in vivo. The adapted virus (G954-V13 differs from its parental strain by only 5 amino acids (4 in P/V/C and 1 in the M gene. While a vaccine strain, Edmonston Zagreb, could replicate equally well in various primate cells, both G954 strains exhibited restriction to the specific cell type used initially for their propagation. Surprisingly, we observed that both G954 strains induced type I IFN, the wt strain inducing even more than the attenuated ones, particularly in human plasmacytoid Dendritic Cells. Type I IFN-induced protection from the infection of both G954 strains depended on the cell type analyzed, being less efficient in the cells used to grow the viral strain. Conclusion Thus, mutations in M and P/V/C proteins can critically affect MV pathogenicity, cellular tropism and lead to virus attenuation without interfering with the α/β IFN system.

  1. CT findings of muscular dystrophy; Limb girdle type (LG), myotonic type (MYD) and Duchenne type (DMD)

    Energy Technology Data Exchange (ETDEWEB)

    Saitoh, Hiroshi (Tokushima Univ. (Japan). School of Medicine)

    1991-07-01

    CT scans of muscles in patients with limb girdle type (LG), myotonic type (MYD) and Duchenne type (DMD) dystrophies were obtained at five different body levels: the neck, L3 vertebral body, pelvic girdle, thigh and lower leg. CT numbers, cross sectional areas (CSA) and %CSA of muscle or fat were evaluated in each muscle. The characteristic CT patterns for each type of muscular dystrophy were obtained. Compared with DMD, the gracilis and soleus were more severely damaged in LG and the biceps femoris remained relatively preserved among the hamstrings. In addition, the multifidus of the neck and sternocleidomastoid also were more severely damaged in MYD. This study suggests that CT scan will be useful in the differential diagnosis of these types of muscular dystrophy as well as in planning appropriate rehabilitation and detecting damaged muscles. (author).

  2. User Types in Online Applications

    Directory of Open Access Journals (Sweden)

    Ion IVAN

    2011-08-01

    Full Text Available Online applications are presented in the context of information society. Online applications characteristics are analyzed. Quality characteristics are presented in relation to online applications users. Types of users for AVIO application are presented. Use cases for AVIO application are identified. The limitations of AVIO application are defined. Types of users in online applications are identified. The threedimensional matrix of access to the online application resources is built. The user type-oriented database is structured. Access management of the fields related to the database tables is analyzed. The classification of online applications users is done.

  3. Types and Forms of Tourism

    Directory of Open Access Journals (Sweden)

    Anca Gabriela Turtureanu

    2008-10-01

    Full Text Available For the study of tourism, the most suitable method from the geographic point of view is typify it, because it allows the delimitation oftourist areas. Tourist areas are characterized by a specific type of travel or by a reunion of some types that may vary dynamically over time. Thetypes of tourism result mainly from the different motivations of the journey, i.e. the purpose of doing. Each type of tourism is distinguished by suchspecific purpose and it is specific to those regions where fixed purpose can be achieved by the existence of some specific facilities.

  4. Modalities in homotopy type theory

    DEFF Research Database (Denmark)

    Rijke, Egbert; Shulman, Michael; Spitters, Bas

    2017-01-01

    Univalent homotopy type theory (HoTT) may be seen as a language for the category of ∞-groupoids. It is being developed as a new foundation for mathematics and as an internal language for (elementary) higher toposes. We develop the theory of factorization systems, reflective subuniverses......, and modalities in homotopy type theory, including their construction using a "localization" higher inductive type. This produces in particular the (n-connected, n-truncated) factorization system as well as internal presentations of subtoposes, through lex modalities. We also develop the semantics...

  5. Type Inference of Turbo Pascal

    DEFF Research Database (Denmark)

    Hougaard, Ole Ildsgaard; Schwartzbach, Michael I; Askari, Hosein

    1995-01-01

    Type inference is generally thought of as being an exclusive property of the functional programming paradigm. We argue that such a feature may be of significant benefit for also standard imperative languages. We present a working tool (available by WWW) providing these benefits for a full version...... of Turbo Pascal. It has the form of a preprocessor that analyzes programs in which the type annotations are only partial or even absent. The resulting program has full type annotations, will be accepted by the standard Turbo Pascal compiler, and has polymorphic use of procedures resolved by means of code...

  6. Polymorphic Types in ACL2

    Directory of Open Access Journals (Sweden)

    Benjamin Selfridge

    2014-06-01

    Full Text Available This paper describes a tool suite for the ACL2 programming language which incorporates certain ideas from the Hindley-Milner paradigm of functional programming (as exemplified in popular languages like ML and Haskell, including a "typed" style of programming with the ability to define polymorphic types. These ideas are introduced via macros into the language of ACL2, taking advantage of ACL2's guard-checking mechanism to perform type checking on both function definitions and theorems. Finally, we discuss how these macros were used to implement features of Specware, a software specification and implementation system.

  7. Diabetes type 2 - meal planning

    Science.gov (United States)

    ... ency/article/007429.htm Diabetes type 2 - meal planning To use the sharing features on this page, ... urac.org). URAC's accreditation program is an independent audit to verify that A.D.A.M. follows ...

  8. Florence Nightingale. Her personality type.

    Science.gov (United States)

    Dossey, B M

    1998-06-01

    The purpose of this article is to cast new and refreshing light on Florence Nightingale's life and work by examining her personality type. Using the theory-based Myers-Briggs Type Indicator (MBTI), the author examines Nightingale's personality type and reveals that she was an introverted-intuitive-thinking-judging (INTJ) type. The merit of using the MBTI is that it allows us to more clearly understand three major areas of Nightingale's life that have been partially unacknowledged or misunderstood: her spiritual development as a practicing mystic, her management of her chronic illness to maintain her prodigious work output, and her chosen strategies to transform her visionary ideas into new health care and social realities.

  9. Lepromatous leprosy of histoid type

    Directory of Open Access Journals (Sweden)

    Annigeri S

    2007-01-01

    Full Text Available Histoid leprosy is a variant of lepromatous leprosy, which develops as a result of resistance to dapsone monotherapy. Here we report two cases of lepromatous leprosy of histoid type, one with typical and another with atypical presentations.

  10. Radioisotope indicator, type BETA 2

    International Nuclear Information System (INIS)

    Duszanski, M.; Pankow, A.; Skwarczynski, B.

    1975-01-01

    The authors describe a radioisotope indicator, type BETA 2, constructed in the ZKMPW Works to be employed in mines for counting, checking, signalling the presence and positioning of cars, as well as monitoring the state of some other equipment. (author)

  11. Allegheny County Soil Type Areas

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset contains soil type and soil classification, by area. Additional info at: http://mcdc.cas.psu.edu/datawiz.htm;...

  12. Living with Type 1 Diabetes

    Science.gov (United States)

    ... Count Glycemic Index Low-Calorie Sweeteners Sugar and Desserts Fitness Exercise & Type 1 Diabetes Get Started Safely ... Balancing nutrition, exercise and proper blood glucose management techniques with the rest of your life's priorities mean ...

  13. Multiple Endocrine Neoplasia Type I

    Science.gov (United States)

    ... hormone (GnRH). GnRH is normally secreted by the hypothalamus and stimulates the pituitary gland to release follicle ... do not require treatment. Treatment of Pancreatic Endocrine Cancer in MEN1 Because the type of pancreatic endocrine ...

  14. Dermatomyositis and Type 1 Interferons

    Science.gov (United States)

    2010-01-01

    Dermatomyositis is a poorly understood multisystem disease predominantly affecting skin and muscle. This review focuses on the potential role of a group of related cytokines, the type 1 interferons, in the pathogenesis of dermatomyositis. Type 1 interferon–inducible transcripts and proteins are uniquely elevated in dermatomyositis muscle compared with all other muscle diseases studied to date. The endothelial cell tubuloreticular inclusions present in affected dermatomyositis muscle are biomarkers of type 1 interferon exposure. The cell-poor lichenoid reaction in skin with predominant involvement of the basal epidermal cell layer and its topologic equivalent in muscle, perifascicular atrophy, may be lesions that develop directly in response to type 1 interferon signaling. PMID:20425524

  15. Types of Haemophilus influenzae Infections

    Science.gov (United States)

    ... Links Global Hib Vaccination Hib Vaccination Meningitis Pneumonia Sepsis Types of Haemophilus influenzae Infections Recommend on Facebook Tweet Share Compartir H. influenzae most often cause pneumonia, but can also cause severe illnesses like ...

  16. Type I Glycogen Storage Disease

    Science.gov (United States)

    ... Legacy Society Make Gifts of Stock Donate Your Car Personal Fundraising Partnership & Support Share Your Story Spread the Word Give While You Shop Contact Us Donate Now Glycogen Storage Disease Type ...

  17. UX Ori-Type Stars

    Science.gov (United States)

    Grinin, V.

    2017-06-01

    The brief review of the properties of the UX Ori type stars is presented. A special attention is given to the results of the Crimean program of the multi-year photometric and polarimetric observations of these stars.

  18. Type IV Wind Turbine Model

    DEFF Research Database (Denmark)

    Hansen, Anca Daniela; Margaris, Ioannis D.

    (WPP) will be considered. The aggregate WPP model, which will be based on the upscaling of the individual wind turbine model on the electrical part, will make use of an equivalent wind speed. The implemented model follows the basic structure of the generic standard Type 4 wind turbine model proposed...... by the International Electrotechnical Commission (IEC), in the IEC61400-27-1 Committee Draft for electrical simulation models for wind power generation, which is currently under review, [1]. The Type 4 wind turbine model described in this report includes a set of adjustments of the standard Type 4 wind turbine model...... project to be incorporated in the wind power plant level. This document describes the Type 4 wind turbine simulation model, implemented in the EaseWind project. The implemented wind turbine model is one of the initial necessary steps toward integrating new control services in the wind power plant level...

  19. Moment Distributions of Phase Type

    DEFF Research Database (Denmark)

    Bladt, Mogens; Nielsen, Bo Friis

    2011-01-01

    Moment distributions of phase-type and matrix-exponential distributions are shown to remain within their respective classes. We provide a probabilistic phase-type representation for the former case and an alternative representation, with an analytically appealing form, for the latter. First order...... moment distributions are of special interest in areas like demography and economics, and we calculate explicit formulas for the Lorenz curve and Gini index used in these disciplines....

  20. Exercise and Type 2 Diabetes

    OpenAIRE

    Colberg, Sheri R.; Sigal, Ronald J.; Fernhall, Bo; Regensteiner, Judith G.; Blissmer, Bryan J.; Rubin, Richard R.; Chasan-Taber, Lisa; Albright, Ann L.; Braun, Barry

    2010-01-01

    Although physical activity (PA) is a key element in the prevention and management of type 2 diabetes, many with this chronic disease do not become or remain regularly active. High-quality studies establishing the importance of exercise and fitness in diabetes were lacking until recently, but it is now well established that participation in regular PA improves blood glucose control and can prevent or delay type 2 diabetes, along with positively affecting lipids, blood pressure, cardiovascular ...