Publications

TitleAbstractYear(sorted ascending)
Filter
PMID
Filter
a proposal for a genome similarity-based taxonomy for plant-pathogenic bacteria that is sufficiently precise to reflect phylogeny, host range, and outbreak affiliation applied to pseudomonas syringae sensu lato as a proof of concept.taxonomy of plant pathogenic bacteria is challenging because pathogens of different crops often belong to the same named species but current taxonomy does not provide names for bacteria below the subspecies level. the introduction of the host range-based pathovar system in the 1980s provided a temporary solution to this problem but has many limitations. the affordability of genome sequencing now provides the opportunity for developing a new genome-based taxonomic framework. we already proposed t ...201727552324
the hopf family of pseudomonas syringae type iii secreted effectors.pseudomonas syringae is a bacterial phytopathogen that utilizes the type iii secretion system to inject effector proteins into plant host cells. pseudomonas syringae can infect a wide range of plant hosts, including agronomically important crops such as tomatoes and beans. the ability of p. syringae to infect such numerous hosts is caused, in part, by the diversity of effectors employed by this phytopathogen. over 60 different effector families exist in p. syringae; one such family is hopf, whic ...201727061875
analysis of the grape (vitis vinifera l.) thaumatin-like protein (tlp) gene family and demonstration that tlp29 contributes to disease resistance.thaumatin-like protein (tlp) is present as a large family in plants, and individual members play different roles in various responses to biotic and abiotic stresses. here we studied the role of 33 putative grape (vitis vinifera l.) tlp genes (vvtlp) in grape disease resistance. heat maps analysis compared the expression profiles of 33 genes in disease resistant and susceptible grape species infected with anthracnose (elsinoe ampelina), powdery mildew (erysiphe necator) or botrytis cinerea. among ...201728655869
different arabidopsis thaliana photosynthetic and defense responses to hemibiotrophic pathogen induced by local or distal inoculation of burkholderia phytofirmans.pathogen infection of plant results in modification of photosynthesis and defense mechanisms. beneficial microorganisms are known to improve plant tolerance to stresses. burkholderia phytofirmans psjn (bp), a beneficial endophytic bacterium, promotes growth of a wide range of plants and induces plant resistance against abiotic and biotic stresses such as coldness and infection by a necrotrophic pathogen. however, mechanisms underlying its role in plant tolerance towards (hemi)biotrophic invaders ...201728840464
structure of c-terminal domain of peptidyl-prolyl cis-trans isomerase from pseudomonas syringae pv. tomato str. dc3000 at 1.6å resolution.peptidyl-prolyl cis-trans isomerase (ppiase) catalyses the conversion between the cis and trans configurations of proline which switches the backbone conformation of peptides. we determined the crystal structure of the c-terminal domain of ppiase from pseudomonas syringae pv. tomato dc3000 (pspto dc3000) at 1.6å resolution. structural comparison of pspto-ppiase with its homologues suggested that the successive arrangement of residues with small side-chain in loop 4 contributes to its substrate s ...201728413971
bacterial and plant natriuretic peptides improve plant defense responses against pathogens.plant natriuretic peptides (pnps) are implicated in the regulation of ions and water homeostasis, and their participation in the plant immune response has been also proposed. xanthomonas citri subsp. citri contains a gene encoding a pnp-like protein (xacpnp) that has no homologues in other bacteria. xacpnp mimics its arabidopsis thaliana homolog atpnp-a by modifying host responses to create favorable conditions for pathogen survival. however, the ability of xacpnp to induce plant defense respons ...201728401640
internalisation of escherichia coli o157:h7 gfp+ in rocket and swiss chard baby leaves as affected by abiotic and biotic damage.internalisation of human pathogens in edible parts of vegetables eaten raw is a major concern, since once internalised they are protected from sanitising treatments. in this study, we examined invasion of gfp-labelled e. coli o157:h7 into intact and biotically (infection with xanthomonas campestris/pseudomonas syringae) and abiotically (grating with silicon carbide) damaged leaves of wild rocket (diplotaxis tenuifolia) and swiss chard (beta vulgaris subsp. cicla) using laser scanning confocal mi ...201728397273
inhibitory effect of thymus vulgaris and origanum vulgare essential oils on virulence factors of phytopatogenic pseudomonas syringae strains.pseudomonas syringae is a phytopathogenic bacterium that causes lesions in the leaves during the colonization process. the damage is associated to the production of many virulence factors such as biofilm and phytotoxins. the essential oils of thymus vulgaris and origanum vulgare have demonstrated the ability to inhibit p. syringae. the aim of this study was to investigate the effects of t. vulgaris and o. vulgare essential oils on the production of virulence factors of phytopatogenic p. syringae ...201728403565
regulation of mir163 and its targets in defense against pseudomonas syringae in arabidopsis thaliana.small rnas are important regulators for a variety of biological processes, including leaf development, flowering-time, embryogenesis and defense responses. mir163 is a non-conserved mirna and its locus has evolved recently through inverted duplication of its target genes to which they belong to the sabath family of related small-molecule methyltransferases (mts). in arabidopsis thaliana, previous study demonstrated that mir163 accumulation was induced by alamethicin treatment, suggesting its rol ...201728401908
identification of circular rnas in kiwifruit and their species-specific response to bacterial canker pathogen invasion.research studies have recently focused on circle rnas (circrnas) in relation to their regulatory functions in animals. however, the systematic identification of circrnas in plants, especially non-model plants, is limited. in addition, raw report on the prediction of the potential role of circrnas in plant response to pathogen invasion is currently available. we conducted the systematic identification of circrnas from four materials originating from three species belonging to genus actinidia unde ...201728396678
four genes essential for recombination define gints, a new type of mobile genomic island widespread in bacteria.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 a ...201728393892
application of surface modified nano ferrite nickel in catalytic reaction (epoxidation of alkenes) and investigation on its antibacterial and antifungal activities.newly, magnetic nanoparticles have extensively been used as alternative catalyst supports, in the view of their high surface area which results in high catalyst loading capacity, high dispersion, low toxicity, environmental preservation, distinguished stability, and suitable catalyst reusing. in the present study, the magnetite nanoparticles, nife2o4@ag and nife2o4@mo, were synthesized and characterized. the antimicrobial activities and catalytic properties of synthesized nanoparticles were test ...201728575933
biosynthesis and evolution of coronafacoyl phytotoxin production in the common scab pathogen streptomyces scabies.coronafacoyl phytotoxins are an important family of plant toxins that are produced by several different phytopathogenic bacteria, including the gammaproteobacterium pseudomonas syringae and the actinobacterium streptomyces scabies. the phytotoxins consist of coronafacic acid (cfa) linked via an amide bond to different amino acids or amino acid derivatives. previous work suggested that s. scabies and p. syringae use distinct biosynthetic pathways for producing cfa, which is subsequently linked to ...201728754703
investigation on the interaction of pseudomonas syringae effector avrpto with atrabe1d gtpase.the tomato bacterial speck is a worldwide disease. it is caused by the infection of pathogenic pseudomonas syringae pv. tomato which delivers the effector avrpto into the host cells via the type iii secretion system. avrpto interacts rab8 subfamily protein in the gtp-bound form and participates in the response to pathogen infection, but the pathogenic mechanism involved by rab8 subfamily remains elusive. here, we investigated on the interrelationship of avrpto8-159 with arabidopsis thaliana gtp- ...201728641564
multiple dictyostelid species destroy biofilms of klebsiella oxytoca and other gram negative species.dictyostelids are free-living phagocytes that feed on bacteria in diverse habitats. when bacterial prey is in short supply or depleted, they undergo multicellular development culminating in the formation of dormant spores. in this work, we tested isolates representing four dictyostelid species from two genera (dictyostelium and polysphondylium) for the potential to feed on biofilms preformed on glass and polycarbonate surfaces. the abilities of dictyostelids were monitored for three hallmarks of ...201728499132
structure-function analysis of the fusarium oxysporum avr2 effector allows uncoupling of its immune-suppressing activity from recognition.plant pathogens employ effector proteins to manipulate their hosts. fusarium oxysporum f. sp. lycopersici (fol), the causal agent of tomato wilt disease, produces effector protein avr2. besides being a virulence factor, avr2 triggers immunity in i-2 carrying tomato (solanum lycopersicum). fol strains that evade i-2 recognition carry point mutations in avr2 (e.g. avr2(r45h) ), but retain full virulence. here we investigate the virulence function of avr2 and determine its crystal structure. transg ...201728857169
survival and electrotransformation of pseudomonas syringae strains under simulated cloud-like conditions.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 bacte ...201728459967
whole transcriptome sequencing of pseudomonas syringae pv. actinidiae-infected kiwifruit plants reveals species-specific interaction between long non-coding rna and coding genes.an outbreak of kiwifruit bacterial canker disease caused by pseudomonas syringae pv. actinidiae (psa) beginning in 2008 caused disaster to the kiwifruit industry. however the mechanisms of interaction between kiwifruit and psa are unknown. long noncoding rnas (lncrnas) are known to regulate many biological processes, but comprehensive repertoires of kiwifruit lncrnas and their effects on the interaction between kiwifruit and psa are unknown. here, based on in-depth transcriptomic analysis of fou ...201728687784
a bacterial acetyltransferase triggers immunity in arabidopsis thaliana independent of hypersensitive response.type-iii secreted effectors (t3es) play critical roles during bacterial pathogenesis in plants. plant recognition of certain t3es can trigger defence, often accompanied by macroscopic cell death, termed the hypersensitive response (hr). economically important species of kiwifruit are susceptible to pseudomonas syringae pv. actinidiae (psa), the causal agent of kiwifruit bacterial canker. although psa is non-pathogenic in arabidopsis thaliana, we observed that a t3e, hopz5 that is unique to a glo ...201728620210
the scientific, economic, and social impacts of the new zealand outbreak of bacterial canker of kiwifruit (pseudomonas syringae pv. actinidiae).the introduction of pseudomonas syringae pv. actinidiae (psa) severely damaged the new zealand kiwifruit industry, which in 2010 was based on only two cultivars. despite an extraordinarily quick and strong response by industry, government, and scientists to minimize the economic and social impacts, the economic consequences of this outbreak were severe. although our understanding of psa epidemiology and control methods increased substantively over the past six years, the kiwifruit industry large ...201728613977
small rna profiling reveals important roles for mirnas in arabidopsis response to bacillus velezensis fzb42.bacillus velezensis fzb42 (previously classified as bacillus amyloliquefaciens fzb42) has been confirmed to successfully colonize plant roots and enhance defense response against pathogen infection. this study indicated that fzb42 inoculation enhanced arabidopsis defense response against pseudomonas syringae dc3000 through inducing the expression of pr1, pdf1.2 and stomata closure. to further clarify the induced defense response at mirna level, srna libraries from arabidopsis roots inoculated wi ...201728754632
the profile and antimicrobial activity of bacillus lipopeptide extracts of five potential biocontrol strains.in this study the efficacy of two different methods for extracting lipopeptides produced by five bacillus strains-ethyl acetate extraction, and acid precipitation followed by methanol extraction-was investigated using mass spectrometry. high performance thin layer chromatography (hptlc) was also used for the simultaneous separation of complex mixtures of lipopeptide extracts and for the determination of antimicrobial activity of their components. the mass spectra clearly showed well-resolved gro ...201728588570
molecular and functional characterization of myxobacteria isolated from soil in india.this study reports the isolation of myxobacteria from soil collected from plains in north india. based on the morphology and 16s rdna sequence, the isolated myxobacteria were identified as corallococcus sp., pyxidicoccus sp., myxococcus sp., cystobacter sp. and archangium sp. the myxobacteria were functionally characterized to assess their ability to produce antibacterial and anticancer metabolites. the isolates were found to be functionally versatile as they produced extracellular bioactive mol ...201728567623
cyclic dipeptides from bacillus vallismortis bs07 require key components of plant immunity to induce disease resistance in arabidopsis against pseudomonas infection.cyclic dipeptides (cdps) are one of the simplest compounds produced by living organisms. plant-growth promoting rhizobacteria (pgprs) also produce cdps that can induce disease resistance. bacillus vallismortis strain bs07 producing various cdps has been evaluated as a potential biocontrol agent against multiple plant pathogens in chili pepper. however, plant signal pathway triggered by cdps has not been fully elucidated yet. here we introduce four cdps, cyclo(gly-l-pro) previously identified fro ...201728811757
wrky70 and its homolog wrky54 negatively modulate the cell wall-associated defenses to necrotrophic pathogens in arabidopsis.previous studies have identified the arabidopsis thaliana transcription factor wrky70 as a node of convergence for salicylic acid (sa) and jasmonic acid (ja)-mediated defense signal pathways and, together with its closest homolog wrky54, as a negative regulator of sa biosynthesis. here, we demonstrate that wrky70 together with wrky54 negatively affect the response of arabidopsis to the necrotrophic pathogens pectobacterium carotovorum and botrytis cinerea, but not to the hemibiotroph pseudomonas ...201728837631
dewax transcription factor is involved in resistance to botrytis cinerea in arabidopsis thaliana and camelina sativa.the cuticle of land plants is the first physical barrier to protect their aerial parts from biotic and abiotic stresses. dewax, an ap2/erf-type transcription factor, negatively regulates cuticular wax biosynthesis. in this study, we investigated the resistance to botrytis cinerea in arabidopsis thaliana and camelina sativa overexpressing dewax and in arabidopsis dewax mutant. compared to wild type (wt) leaves, arabidopsis dewax ox and dewax leaves were more and less permeable to toluidine blue d ...201728744297
gbf1 differentially regulates cat2 and pad4 transcription to promote pathogen defense in arabidopsis thaliana.g-box binding factor 1 (gbf1) influences light-regulated seedling development in arabidopsis, and inhibits catalase 2 (cat2) expression during senescence. cat2 functions as a scavenger of hydrogen peroxide. the role of gbf1 in the defense response is not known. we report here that gbf1 positively influences the defense against virulent and avirulent strains of pseudomonas syringae. the gbf1 mutants are susceptible, whereas gbf1 over-expresser transgenic plants are resistant to bacterial pathogen ...201728622438
a one-step procedure for immobilising the thermostable carbonic anhydrase (sspca) on the surface membrane of escherichia coli.the carbonic anhydrase superfamily (ca, ec 4.2.1.1) of metalloenzymes is present in all three domains of life (eubacteria, archaea, and eukarya), being an interesting example of convergent/divergent evolution, with its seven families (α-, β-, γ-, δ-, ζ-, η-, and θ-cas) described so far. cas catalyse the simple, but physiologically crucial reaction of carbon dioxide hydration to bicarbonate and protons. recently, our groups characterised the α-ca from the thermophilic bacterium, sulfurihydrogenib ...201728791907
the powdery mildew-resistant arabidopsis mlo2 mlo6 mlo12 triple mutant displays altered infection phenotypes with diverse types of phytopathogens.arabidopsis thaliana mlo2 mlo6 mlo12 triple mutant plants exhibit complete immunity against infection by otherwise virulent obligate biotrophic powdery mildew fungi such as golovinomyces orontii. while this phenotype is well documented, the interaction profile of the triple mutant with other microbes is underexplored and incomplete. here, we thoroughly assessed and quantified the infection phenotypes of two independent powdery mildew-resistant triple mutant lines with a range of microbes. these ...201728839137
expression of hopai interferes with map kinase signalling in magnaporthe oryzae.the pmk1 and mps1 map kinases are essential for appressorium formation and plant infection in magnaporthe oryzae. however, their exact roles during invasive growth are not clear because pmk1 and mps1 mutants are defective in penetration. to further characterize their functions after penetration, in this study we expressed the pseudomonas syringae effector hopai known to inactivate plant map kinases in m. oryzae. constitutive expression of hopai with the rp27 or trpc promoter resulted in defects ...201728799700
rational design of cyclic antimicrobial peptides based on bpc194 and bpc198.a strategy for the design of antimicrobial cyclic peptides derived from the lead compounds c(kklkkfkklq) (bpc194) and c(klkkkfkklq) (bpc198) is reported. first, the secondary β-structure of bpc194 and bpc198 was analyzed by carrying out molecular dynamics (md) simulations. then, based on the sequence pattern and the β-structure of bpc194 or bpc198, fifteen analogues were designed and synthesized on solid-phase. the best peptides (bpc490, bpc918, and bpc924) showed minimum inhibitory concentratio ...201728672817
alteration of cell wall xylan acetylation trigger defense responses that counterbalance the immune deficiencies of plants impaired in the β subunit of the heterotrimeric g protein.arabidopsis heterotrimeric g protein complex modulates pathogen associated molecular pattern-triggered immunity (pti) and disease resistance responses to different type of pathogens. it also plays a role in plant cell wall integrity as mutants impaired in the gβ (agb1-2) or gγ subunits have an altered wall composition compared to wild-type plants. here we performed a mutant screen to identify suppressors of agb1-2 (sgb) that restore susceptibility to pathogens to wild-type levels. out of the fou ...201728792629
silencing of atrap, a target gene of a bacteria-induced small rna, triggers antibacterial defense responses through activation of lsu2 and down-regulation of glk1.plants fine-tune their sophisticated immunity systems in response to pathogen infections. we previously showed that atlsirna-1, a bacteria-induced plant endogenous small interfering rna, silences the atrap gene, which encodes a putative rna binding protein. in this study, we demonstrate that atrap functions as a negative regulator in plant immunity by characterizing molecular and biological responses of the knockout mutant and overexpression lines of atrap upon bacterial infection. atrap is loca ...201728656601
effects of colonization of a bacterial endophyte, azospirillum sp. b510, on disease resistance in tomato.a plant growth-promoting bacteria, azospirillum sp. b510, isolated from rice, can enhance growth and yield and induce disease resistance against various types of diseases in rice. because little is known about the interaction between other plant species and this strain, we have investigated the effect of its colonization on disease resistance in tomato plants. treatment with this strain by soil-drenching method established endophytic colonization in root tissues in tomato plant. the endophytic c ...201728569642
seasonal variation in phytochemicals and nutraceutical potential of begonia nelumbiifolia consumed in puebla, méxico.begonia nelumbiifolia is a traditional edible plant consumed and commercialized in the northern highlands of puebla, méxico. the present study reports the seasonal variation in proximate analysis as well as organic acids, carotenoids and flavonoids content in both leaves and stalks of this plant. the stalks contained low concentrations of protein (~3%), fiber (~1.5%) and nitrogen free extract (~0.26%) during the time of study. both organs showed contents of oxalic acid (91-103 mg 100 g(-1) fw), ...201728559607
testing differences between pathogen compositions with small samples and sparse data.the structure of pathogen populations is an important driver of epidemics affecting crops and natural plant communities. comparing the composition of two pathogen populations consisting of assemblages of genotypes or phenotypes is a crucial, recurrent question encountered in many studies in plant disease epidemiology. determining whether there is a significant difference between two sets of proportions is also a generic question for numerous biological fields. when samples are small and data are ...201728677479
network analysis reveals a common host-pathogen interaction pattern in arabidopsis immune responses.many plant pathogens secrete virulence effectors into host cells to target important proteins in host cellular network. however, the dynamic interactions between effectors and host cellular network have not been fully understood. here, an integrative network analysis was conducted by combining arabidopsis thaliana protein-protein interaction network, known targets of pseudomonas syringae and hyaloperonospora arabidopsidis effectors, and gene expression profiles in the immune response. in particu ...201728611808
dissecting virulence function from recognition: cell death suppression in nicotiana benthamiana by xopq/hopq1-family effectors relies on eds1-dependent immunity.many gram-negative plant pathogenic bacteria express effector proteins of the xopq/hopq1 family which are translocated into plant cells via the type iii secretion system during infection. in nicotiana benthamiana, recognition of xopq/hopq1 proteins induces an effector-triggered immunity (eti) reaction which is not associated with strong cell death but renders plants immune against pseudomonas syringae and xanthomonas campestris pv. vesicatoria strains. additionally, xopq suppresses cell death in ...201728423458
resistance to powdery mildew8.1 boosts pattern-triggered immunity against multiple pathogens in arabidopsis and rice.the arabidopsis gene resistance to powdery mildew8.1 (rpw8.1) confers resistance to virulent fungal and oomycete pathogens that cause powdery mildew and downy mildew, respectively. however, the underlying mechanism remains unclear. here, we show that ectopic expression of rpw8.1 boosts pattern-triggered immunity (pti) resulting in enhanced resistance against different pathogens in both arabidopsis and rice. in arabidopsis, transcriptome analysis revealed that ectopic expression of rpw8.1-yfp con ...201728640974
sde5, a putative rna export protein, participates in plant innate immunity through a flagellin-dependent signaling pathway in arabidopsis.in eukaryotes, rna silencing, mediated by small interfering rnas, is an evolutionarily widespread and versatile silencing mechanism that plays an important role in various biological processes. increasing evidences suggest that various components of rna silencing pathway are involved in plant defense machinery against microbial pathogens in arabidopsis thaliana. here, we show genetic and molecular evidence that arabidopsis sde5 is required to generate an effective resistance against the biotroph ...201728851870
the ferric uptake regulator fur is conditionally essential in pseudomonas aeruginosa.in pseudomonas aeruginosa the ferric uptake regulator protein (fur) controls both metabolism and virulence in response to iron availability. differently from other bacteria, attempts to obtain fur deletion mutants in p. aeruginosa failed, leading to the assumption that fur is an essential protein in this bacterium. by investigating a p. aeruginosa fur conditional mutant, we demonstrate that fur is not essential for p. aeruginosa growth in liquid media, biofilm formation, and pathogenicity in an ...201728847923
in-silico taxonomic classification of 373 genomes reveals species misidentification and new genospecies within the genus pseudomonas.the genus pseudomonas has one of the largest diversity of species within the bacteria kingdom. to date, its taxonomy is still being revised and updated. due to the non-standardized procedure and ambiguous thresholds at species level, largely based on 16s rrna gene or conventional biochemical assay, species identification of publicly available pseudomonas genomes remains questionable. in this study, we performed a large-scale analysis of all pseudomonas genomes with species designation (excluding ...201728747902
studies on the o-specific polysaccharide of the lipopolysaccharide from the pseudomonas mediterranea strain c5p1rad1, a bacterium pathogenic of tomato and chrysanthemum.an o-specific polysaccharide (ops) was isolated from the lipopolysaccharide of pseudomonas mediterranea strain c5p1rad1, the causal agents of tomato pith necrosis and chrysanthemum stem rot, and studied by one- and two-dimensional (1)h and (13)c nmr spectroscopy. the following structure of the trisaccharide repeating unit of the ops was established, which, to our knowledge, is unique among the known bacterial polysaccharide structures: →4)-β-d-manpnac3naca-(1 → 4)-β-d-manpnac3naca-(1 → 3)-α-d-qu ...201728601025
suppression of plant immune responses by the pseudomonas savastanoi pv. savastanoi ncppb 3335 type iii effector tyrosine phosphatases hopao1 and hopao2.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 ...201728529516
microbial degradation of lobster shells to extract chitin derivatives for plant disease management.biodegradation of lobster shells by chitinolytic microorganisms are an environment safe approach to utilize lobster processing wastes for chitin derivation. in this study, we report degradation activities of two microbes, "s223" and "s224" isolated from soil samples that had the highest rate of deproteinization, demineralization and chitinolysis among ten microorganisms screened. isolates s223 and s224 had 27.3 and 103.8 protease units mg(-1) protein and 12.3 and 11.2 μg ml(-1) of calcium in the ...201728529501
global temporal dynamic landscape of pathogen-mediated subversion of arabidopsis innate immunity.the universal nature of networks' structural and physical properties across diverse systems offers a better prospect to elucidate the interplay between a system and its environment. in the last decade, several large-scale transcriptome and interactome studies were conducted to understand the complex and dynamic nature of interactions between arabidopsis and its bacterial pathogen, pseudomonas syringae pv. tomato dc3000. we took advantage of these publicly available datasets and performed "-omics ...201728798368
holaphyllamine, a steroid, is able to induce defense responses in arabidopsis thaliana and increases resistance against bacterial infection.a chemical screen of plant-derived compounds identified holaphyllamine, a steroid, able to trigger defense responses in arabidopsis thaliana and improve resistance against the pathogenic bacterium pseudomonas syringae pv tomato dc3000. a chemical screen of 1600 plant-derived compounds was conducted and allowed the identification of a steroid able to activate defense responses in a. thaliana at a concentration of 1 µm without altering growth. the identified compound is holaphyllamine (hpa) whose ...201728815300
age-related resistance in arabidopsis thaliana involves the mads-domain transcription factor short vegetative phase and direct action of salicylic acid on pseudomonas syringae.arabidopsis thaliana exhibits a developmentally regulated disease-resistance response known as age-related resistance (arr), a process that requires intercellular accumulation of salicylic acid (sa), which is thought to act as an antimicrobial agent. arr is characterized by enhanced resistance to some pathogens at the late adult-vegetative and reproductive stages. while the transition to flowering does not cause the onset of arr, both processes involve the mads-domain transcription factor short ...201728812948
prr2, a pseudo-response regulator, promotes salicylic acid and camalexin accumulation during plant immunity.calcium signalling mediated by calmodulin (cam) and calmodulin-like (cml) proteins is critical to plant immunity. cam and cml regulate a wide range of target proteins and cellular responses. while many cam-binding proteins have been identified, few have been characterized for their specific role in plant immunity. here, we report new data on the biological function of a cml-interacting partner, prr2 (pseudo-response regulator 2), a plant specific transcription factor. until now, the physiologica ...201728765536
the accumulation of β-aminobutyric acid is controlled by the plant's immune system.endogenous levels of β-aminobutyric acid (baba) increase after the molecular recognition of pathogen presence. baba is accumulated differently during resistance or susceptibility to disease. the priming molecule β-aminobutyric acid has been recently shown to be a natural product of plants, and this has provided significance to the previous discovery of a perception mechanism in arabidopsis. baba levels were found to increase after abiotic stress or infection with virulent pathogens, but the role ...201728762076
occurrence and epidemics of bacterial canker of kiwifruit in korea.bacterial canker is the largest limiting factor in the cultivation and production of kiwifruit worldwide. typical symptoms comprise necrotic spots on leaves, canker and dieback on canes and trunks, twig wilting, and blossom necrosis. pseudomonas syringae pv. actinidiae (psa), which is the causal agent of kiwifruit bacterial canker, is divided into four biovars based on multilocus sequence analysis of different genes, additional pcr testing of pathogenic genes (argktox cluster, cfl, and various e ...201728811752
a plant effector-triggered immunity signaling sector is inhibited by pattern-triggered immunity.since signaling machineries for two modes of plant-induced immunity, pattern-triggered immunity (pti) and effector-triggered immunity (eti), extensively overlap, pti and eti signaling likely interact. in an arabidopsis quadruple mutant, in which four major sectors of the signaling network, jasmonate, ethylene, pad4, and salicylate, are disabled, the hypersensitive response (hr) typical of eti is abolished when the pseudomonas syringae effector avrrpt2 is bacterially delivered but is intact when ...201728811287
structures and mechanisms of the non-heme fe(ii)- and 2-oxoglutarate-dependent ethylene-forming enzyme: substrate binding creates a twist.the ethylene-forming enzyme (efe) from pseudomonas syringae pv. phaseolicola pk2 is a member of the mononuclear nonheme fe(ii)- and 2-oxoglutarate (2og)-dependent oxygenase superfamily. efe converts 2og into ethylene plus three co2 molecules while also catalyzing the c5 hydroxylation of l-arginine (l-arg) driven by the oxidative decarboxylation of 2og to form succinate and co2. here we report 11 x-ray crystal structures of efe that provide insight into the mechanisms of these two reactions. bind ...201728780854
the sal-pap chloroplast retrograde pathway contributes to plant immunity by regulating glucosinolate pathway and phytohormone signaling.chloroplasts have a crucial role in plant immunity against pathogens. increasing evidence suggests that phytopathogens target chloroplast homeostasis as a pathogenicity mechanism. in order to regulate the performance of chloroplasts under stress conditions, chloroplasts produce retrograde signals to alter nuclear gene expression. many signals for the chloroplast retrograde pathway have been identified, including chlorophyll intermediates, reactive oxygen species, and metabolic retrograde signals ...201728703028
a novel family of proline/serine-rich proteins, which are phospho-targets of stress-related mitogen-activated protein kinases, differentially regulates growth and pathogen defense in arabidopsis thaliana.the molecular actions of mitogen-activated protein kinases (mapks) are ultimately accomplished by the substrate proteins where phosphorylation affects their molecular properties and function(s), but knowledge regarding plant mapk substrates is currently still fragmentary. here, we uncovered a previously uncharacterized protein family consisting of three proline/serine-rich proteins (prps) that are substrates of stress-related mapks. we demonstrated the importance of a mapk docking domain necessa ...201728755319
pseudomonas predators: understanding and exploiting phage-host interactions.species in the genus pseudomonas thrive in a diverse set of ecological niches and include crucial pathogens, such as the human pathogen pseudomonas aeruginosa and the plant pathogen pseudomonas syringae. the bacteriophages that infect pseudomonas spp. mirror the widespread and diverse nature of their hosts. therefore, pseudomonas spp. and their phages are an ideal system to study the molecular mechanisms that govern virus-host interactions. furthermore, phages are principal catalysts of host evo ...201728649138
draft genome sequence of pseudomonas syringae pdd-32b-74, a model strain for ice-nucleation studies in the atmosphere.we report here the whole genome sequence of pseudomonas syringae pdd-32b-74, a gammaproteobacterium isolated from cloud water. this microorganism is equipped with ice-nucleation protein and biosurfactant genes that could potentially be involved in physicochemical processes in the atmosphere and clouds.201728751406
constitutive activity of the arabidopsis map kinase 3 confers resistance to pseudomonas syringae and drives robust immune responses.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 ...201728766995
genome-wide linkage and association mapping of halo blight resistance in common bean to race 6 of the globally important bacterial pathogen.pseudomonas syringae pv. phaseolicola (psph) race 6 is a globally prevalent and broadly virulent bacterial pathogen with devastating impact causing halo blight of common bean (phaseolus vulgaris l.). common bean lines pi 150414 and cal 143 are known sources of resistance against this pathogen. we constructed high-resolution linkage maps for three recombinant inbred populations to map resistance to psph race 6 derived from the two common bean lines. this was complemented with a genome-wide associ ...201728736566
knots untie: molecular determinants involved in knot formation induced by pseudomonas savastanoi in woody hosts.the study of the molecular basis of tree diseases is lately receiving a renewed attention, especially with the emerging perception that pathogens require specific pathogenicity and virulence factors to successfully colonize woody hosts. pathosystems involving woody plants are notoriously difficult to study, although the use of model bacterial strains together with genetically homogeneous micropropagated plant material is providing a significant impetus to our understanding of the molecular deter ...201728680437
sg2-type r2r3-myb transcription factor myb15 controls defense-induced lignification and basal immunity in arabidopsis.lignification of cell wall appositions is a conserved basal defense mechanism in the plant innate immune response. however, the genetic pathway controlling defense-induced lignification remains unknown. here, we demonstrate the arabidopsis thaliana sg2-type r2r3-myb transcription factor myb15 as a regulator of defense-induced lignification and basal immunity. loss of myb15 reduces the content but not the composition of defense-induced lignin, whereas constitutive expression of myb15 increases li ...201728733420
transcriptome changes in arabidopsis thaliana infected with pseudomonas syringae during drought recovery.field-grown plants experience cycles of drought stress and recovery due to variation in soil moisture status. physiological, biochemical and transcriptome responses instigated by recovery are expected to be different from drought stress and non-stressed state. such responses can further aid or antagonize the plant's interaction with the pathogen. however, at molecular level, not much is known about plant-pathogen interaction during drought recovery. in the present study, we performed a microarra ...201728831155
plc2 regulates mamp-triggered immunity by modulating ros production in arabidopsis.the activation of phosphoinositide-specific phospholipase c (pi-plc) is one of the earliest responses triggered by the recognition of several microbe-associated molecular patterns (mamps) in plants. the arabidopsis pi-plc gene family is composed of nine members. previous studies suggested a role for plc2 in mamp-triggered immunity (mti) as it is rapidly phosphorylated in vivo upon treatment with the bacterial mamp flg22. here we analyzed the role of plc2 in plant immunity using an artificial mic ...201728827453
phytohormone and putative defense gene expression differentiates the response of 'hayward' kiwifruit to psa and pfm infections.pseudomonas syringae pv. actinidiae (psa) and pseudomonas syringae pv. actinidifoliorum (pfm) are closely related pathovars infecting kiwifruit, but psa is considered one of the most important global pathogens, whereas pfm is not. in this study of actinidia deliciosa 'hayward' responses to the two pathovars, the objective was to test whether differences in plant defense responses mounted against the two pathovars correlated with the contrasting severity of the symptoms caused by them. results sh ...201728824694
a conserved ear motif is required for avirulence and stability of the ralstonia solanacearum effector popp2 in planta.ralstonia solanacearum is the causal agent of the devastating bacterial wilt disease in many high value solanaceae crops. r. solanacearum secretes around 70 effectors into host cells in order to promote infection. plants have, however, evolved specialized immune receptors that recognize corresponding effectors and confer qualitative disease resistance. in the model species arabidopsis thaliana, the paired immune receptors rrs1 (resistance to ralstonia solanacearum 1) and rps4 (resistance to pseu ...201728824668
photochemical formation of chitosan-stabilized near-infrared-absorbing silver nanoworms: a "green" synthetic strategy and activity on gram-negative pathogenic bacteria.a facile, single-step, non-seeded photochemical protocol for producing a new type of anisotropic silver nanostructure, "nanoworms", with curved longer dimensions and smooth, rounded edges. the nanoworms exhibit surface plasmon resonance (spr) absorption in the near-infrared window (nirw) region and are stabilized using biocompatible polymer chitosan, rendering biocompatibility and amplified safety for biological utility of the composition. both nirw-absorbing nanoworms and visible-absorbing nano ...201728810197
a non-targeted metabolomics approach unravels the vocs associated with the tomato immune response against pseudomonas syringae.volatile organic compounds (vocs) emitted by plants are secondary metabolites that mediate the plant interaction with pathogens and herbivores. these compounds may perform direct defensive functions, i.e., acting as antioxidant, antibacterial, or antifungal agents, or indirectly by signaling the activation of the plant's defensive responses. using a non-targeted gc-ms metabolomics approach, we identified the profile of the vocs associated with the differential immune response of the rio grande t ...201728725238
signaling from the plasma-membrane localized plant immune receptor rpm1 requires self-association of the full-length protein.plants evolved intracellular immune receptors that belong to the nod-like receptor (nlr) family to recognize the presence of pathogen-derived effector proteins. nlrs possess an n-terminal toll-like/il-1 receptor (tir) or a non-tir domain [some of which contain coiled coils (ccs)], a central nucleotide-binding (nb-arc) domain, and a c-terminal leucine-rich repeat (lrr). activation of nlr proteins results in a rapid and high-amplitude immune response, eventually leading to host cell death at the i ...201728808003
tyrosine-610 in the receptor kinase bak1 does not play a major role in brassinosteroid signaling or innate immunity.the plasma membrane-localized bri1-associated kinase1 (bak1) functions as a co-receptor with several receptor kinases including the brassinosteroid (br) receptor brassinosteroid-insensitive 1 (bri1), which is involved in growth, and the receptors for bacterial flagellin and ef-tu, flagellin-sensing 2 (fls2) and ef-tu receptor (efr), respectively, which are involved in immunity. bak1 is a dual specificity protein kinase that can autophosphorylate on serine, threonine and tyrosine residues. it was ...201728824659
stomate-based defense and environmental cues.environmental conditions play crucial roles in modulating immunity and disease in plants. for instance, many bacterial disease outbreaks occur after periods of high humidity and rain. a critical step in bacterial infection is entry into the plant interior through wounds or natural openings, such as stomata. bacterium-triggered stomatal closure is an integral part of the plant immune response to reduce pathogen invasion. recently, we found that high humidity compromises stomatal defense, which is ...201728816601
comparative study of arabidopsis pbs1 and a wheat pbs1 homolog helps understand the mechanism of pbs1 functioning in innate immunity.arabidopsis avrpphb susceptible1 (pbs1) serves as a "decoy" in activating resistance to pseudomonas syringae5 (rps5) upon cleavage by pseudomonas phaseolicola b (avrpphb), a pseudomonas syringae effector. the semph motif in pbs1 was thought to allow it to be distinguished by rps5 from the closely related arabidopsis kinases. however, the underlying mechanism is not fully understood. here, we isolated and characterized a wheat pbs1 homolog, tapbs1. although this plasma membrane-localized kinase c ...201728710392
the ecf sigma factor, pspto_1043, in pseudomonas syringae pv. tomato dc3000 is induced by oxidative stress and regulates genes involved in oxidative stress response.the bacterial plant pathogen pseudomonas syringae adapts to changes in the environment by modifying its gene expression profile. in many cases, the response is mediated by the activation of extracytoplasmic function (ecf) sigma factors that direct rna polymerase to transcribe specific sets of genes. in this study we focus on pspto_1043, one of ten ecf sigma factors in p. syringae pv. tomato dc3000 (dc3000). pspto_1043, together with pspto_1042, encode an rpoersp/chrr-like sigma/anti-sigma factor ...201728700608
a rapid seedling resistance assay identifies wild tomato lines that are resistant to pseudomonas syringae pv. tomato race 1.bacterial speck caused by pseudomonas syringae has historically been controlled by the pto/prf gene cluster. emerging strains like p. syringae pv. tomato race 1 overcome resistance conferred by pto/prf, and can cause serious crop loss under appropriate environmental conditions. we developed a rapid assay to screen wild tomato seedlings for resistance to p. syringae pv. tomato race 1. we established the seedling resistance assay using the well-characterized p. syringae pv. tomato race 0 strain, d ...201728517960
a calmodulin-like protein regulates plasmodesmal closure during bacterial immune responses.plants sense microbial signatures via activation of pattern recognition receptors (pprs), which trigger a range of cellular defences. one response is the closure of plasmodesmata, which reduces symplastic connectivity and the capacity for direct molecular exchange between host cells. plasmodesmal flux is regulated by a variety of environmental cues but the downstream signalling pathways are poorly defined, especially the way in which calcium regulates plasmodesmal closure. here, we identify that ...201728513846
an hplc-based method to quantify coronatine production by bacteria.coronatine is a polyketide phytotoxin produced by several pathovars of the plant pathogenic bacterium pseudomonas syringae. it is one of the most important virulence factors determining the success of bacterial pathogenesis in the plant at both epiphytic and endophytic stages of the disease cycle. this protocol describes an optimized procedure to culture bacterial cells for coronatine production and to quantify the amount of coronatine secreted in the culture medium using an hplc-based method.201728516126
bio-fabrication of silver nanoparticles using the leaf extract of an ancient herbal medicine, dandelion (taraxacum officinale), evaluation of their antioxidant, anticancer potential, and antimicrobial activity against phytopathogens.in recent years, the use of nanoparticle-based antimicrobials has been increased due to many advantages over conventional agrochemicals. this study investigates the utilization of common medicinal plant dandelion, taraxacum officinale, for the synthesis of silver nanoparticles (tol-agnps). agnps were evaluated for antimicrobial activity against two important phytopathogens, xanthomonas axonopodis and pseudomonas syringae. the morphology, size, and structure of tol-agnps were characterized using ...201728699009
a lectin receptor-like kinase mediates pattern-triggered salicylic acid signaling.plant surface-localized pathogen recognition receptors (prrs) perceive conserved microbial features, termed pathogen-associated molecular patterns (pamps), resulting in disease resistance. pamp perception leads to calcium influx, mapk activation, a burst of reactive oxygen species (ros) mediated by rbohd, accumulation of the defense hormone salicylic acid (sa), and callose deposition. lectin receptor-like kinases (lecrks) belong to a specific prr family and are important players in plant innate ...201728696275
an essential role for the vast domain of the arabidopsis vad1 protein in the regulation of defense and cell death in response to pathogens.several regulators of programmed cell death (pcd) have been identified in plants which encode proteins with putative lipid-binding domains. among them, vad1 (vascular associated death) contains a novel protein domain called vast (vad1 analog star-related lipid transfer) still uncharacterized. the arabidopsis mutant vad1-1 has been shown to exhibit a lesion mimic phenotype with light-conditional appearance of propagative hypersensitive response-like lesions along the vascular system, associated w ...201728683084
pseudomonas syringae pv. tomato dc3000 polymutants deploying coronatine and two type iii effectors produce quantifiable chlorotic spots from individual bacterial colonies in nicotiana benthamiana leaves.primary virulence factors of pseudomonas syringae pv. tomato dc3000 include the phytotoxin coronatine (cor) and a repertoire of 29 effector proteins injected into plant cells by the type iii secretion system (t3ss). dc3000 derivatives differentially producing cor, the t3ss machinery, and subsets of key effectors were constructed and assayed in leaves of nicotiana benthamiana. bacteria were inoculated by dipping of whole plants and assayed for population growth and production of chlorotic spots o ...201728677296
analysis of the zar1 immune complex reveals determinants for immunity and molecular interactions.plants depend on innate immunity to prevent disease. plant pathogenic bacteria, like pseudomonas syringae and xanthomonas campestris, use the type iii secretion system as a molecular syringe to inject type iii secreted effector (t3se) proteins in plants. the primary function of most t3ses is to suppress immunity; however, the plant can evolve nucleotide-binding domain-leucine-rich repeat domain-containing proteins to recognize specific t3ses. the atzar1 nlr induces strong defense responses again ...201728652264
jmj27, an arabidopsis h3k9 histone demethylase, modulates defense against pseudomonas syringae and flowering time.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 dom ...201728650521
regulation of growth-defense balance by the jasmonate zim-domain (jaz)-myc transcriptional module.the plant hormone jasmonate (ja) promotes the degradation of jasmonate zim-domain (jaz) proteins to relieve repression on diverse transcription factors (tfs) that execute ja responses. however, little is known about how combinatorial complexity among jaz-tf interactions maintains control over myriad aspects of growth, development, reproduction, and immunity. we used loss-of-function mutations to define epistatic interactions within the core ja signaling pathway and to investigate the contributio ...201728649719
say hello to my little friends: how microbiota can modulate tree health. 201728631327
spatiotemporal monitoring of pseudomonas syringae effectors via type iii secretion using split fluorescent protein fragments.pathogenic gram-negative bacteria cause serious diseases in animals and plants. these bacterial pathogens use the type iii secretion system (t3ss) to deliver effector proteins into host cells; these effectors then localize to different subcellular compartments to attenuate immune responses by altering biological processes of the host cells. the fluorescent protein (fp)-based approach to monitor effectors secreted from bacteria into the host cells is not possible because the folded fp prevents ef ...201728619883
interplay of pathogen-induced defense responses and symbiotic establishment in medicago truncatula.suppression of host innate immunity appears to be required for the establishment of symbiosis between rhizobia and host plants. in this study, we established a system that included a host plant, a bacterial pathogen and a symbiotic rhizobium to study the role of innate immunity during symbiotic interactions. a pathogenic bacterium, pseudomonas syringae pv. tomato strain dc3000 (pst dc3000), was shown to cause chlorosis in medicago truncatula a17. sinorhizobium meliloti strain sm2011 (sm2011) and ...201728611764
direct and indirect visualization of bacterial effector delivery into diverse plant cell types during infection.to cause disease, diverse pathogens deliver effector proteins into host cells. pathogen effectors can inhibit defense responses, alter host physiology, and represent important cellular probes to investigate plant biology. however, effector function and localization have primarily been investigated after overexpression in planta. visualizing effector delivery during infection is challenging due to the plant cell wall, autofluorescence, and low effector abundance. here, we used a gfp strand system ...201728600390
correction to biochemical and spectroscopic characterization of the non-heme fe(ii)- and 2-oxoglutarate-dependent ethylene-forming enzyme from pseudomonas syringae pv. phaseolicola pk2. 201728590751
surface inoculation and quantification of pseudomonas syringae population in the arabidopsis leaf apoplast.bacterial pathogens must enter the plant tissue in order to cause a successful infection. foliar bacterial pathogens that are not able to directly penetrate the plant epidermis rely on wounds or natural openings to internalize leaves. this protocol describes a procedure to estimate the population size of pseudomonas syringae in the leaf apoplast after surface inoculation of arabidopsis rosettes.201728573169
temperature-mediated biosynthesis of the phytotoxin phaseolotoxin by pseudomonas syringae pv. phaseolicola depends on the autoregulated expression of the phtabc genes.pseudomonas syringae pv. phaseolicola produces phaseolotoxin in a temperature dependent manner, being optimally synthesized between 18°c and 20°c, while no detectable amounts are present above 28°c. the pht cluster, involved in the biosynthesis of phaseolotoxin, contains 23 genes that are organized in five transcriptional units. the function of most of the genes from the pht cluster is still unknown and little information about the regulatory circuitry leading to expression of these genes has be ...201728570637
atmospheric co2 alters resistance of arabidopsis to pseudomonas syringae by affecting abscisic acid accumulation and stomatal responsiveness to coronatine.atmospheric co2 influences plant growth and stomatal aperture. effects of high or low co2 levels on plant disease resistance are less well understood. here, resistance of arabidopsis thaliana against the foliar pathogen pseudomonas syringae pv. tomato dc3000 (pst) was investigated at three different co2 levels: high (800 ppm), ambient (450 ppm), and low (150 ppm). under all conditions tested, infection by pst resulted in stomatal closure within 1 h after inoculation. however, subsequent stomatal ...201728559899
pseudomonas caspiana sp. nov., a citrus pathogen in the pseudomonas syringae phylogenetic group.in a screening by multilocus sequence analysis of pseudomonas strains isolated from diverse origins, 4 phylogenetically closely related strains (fbf58, fbf102(t), fbf103, and fbf122) formed a well-defined cluster in the pseudomonas syringae phylogenetic group. the strains were isolated from citrus orchards in northern iran with disease symptoms in the leaves and stems and its pathogenicity against citrus plants was demonstrated. the whole genome of the type strain of the proposed new species (fb ...201728552245
cbl-interacting protein kinase 6 negatively regulates immune response to pseudomonas syringae in arabidopsis.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 ...201728541442
the tomato kinase pti1 contributes to production of reactive oxygen species in response to two flagellin-derived peptides and promotes resistance to pseudomonas syringae infection.the pti1 kinase was identified from a reverse genetic screen as contributing to pattern-triggered immunity (pti) against pseudomonas syringae pv. tomato (pst). the tomato genome has two pti1 genes, referred to as pti1a and pti1b. a hairpin-pti1 (hppti1) construct was developed and was used to generate two independent stable transgenic tomato lines that had reduced transcript abundance of both genes. in response to p. syringae pv. tomato inoculation, these hppti1 plants developed more severe dise ...201728535079
transgenerational defense priming for crop protection against plant pathogens: a hypothesis.throughout evolution, plants have developed diverse mechanisms of defense that "prime" their innate immune system for more robust and active induction of defense responses against different types of stress. nowadays there are numerous reports concerning the molecular bases of priming, as well as the generational priming mechanisms. information concerning transgenerational priming, however, remains deficient. some reports have indicated, nonetheless, that the priming status of a plant can be inhe ...201728523009
genetic interaction between arabidopsis qpm3.1 locus and bacterial effector gene hopw1-1 underlies natural variation in quantitative disease resistance to pseudomonas infection.wide quantitative variation in plant disease resistance across arabidopsis wild populations has been documented and the underlying mechanisms remain largely unknown. to investigate the genetic and molecular basis of this variation, arabidopsis recombinant inbred lines (rils) derived from aa-0 × col-0 and gie-0 × col-0 crosses were constructed and used for inoculation with pseudomonas syringae pathovars maculicola es4326 (es4326) and tomato dc3000 (dc3000). bacterial growth assays revealed contin ...201728523008
flagellin peptide flg22 gains access to long-distance trafficking in arabidopsis via its receptor, fls2.diverse pathogen-derived molecules, such as bacterial flagellin and its conserved peptide flg22, are recognized in plants via plasma membrane receptors and induce both local and systemic immune responses. the fate of such ligands was unknown: whether and by what mechanism(s) they enter plant cells and whether they are transported to distal tissues. we used biologically active fluorophore and radiolabeled peptides to establish that flg22 moves to distal organs with the closest vascular connection ...201728521013
effector translocation: cya reporter assay.an accurate and complete roster of the type iii effector (t3e) proteins translocated by the p. syringae type iii secretion system (t3ss) into host cells is critical to understanding the pathogen's interactions with plants. the adenylate cyclase (cya) reporter offers a highly sensitive and robust assay for monitoring the translocation of t3es. t3es are fused to the calmodulin-dependent adenylate-cyclase domain of cyaa. the t3e targets cya for translocation through the t3ss into the host cell at w ...201728667631
pathogen exploitation of an abscisic acid- and jasmonate-inducible mapk phosphatase and its interception by arabidopsis immunity.phytopathogens promote virulence by, for example, exploiting signaling pathways mediated by phytohormones such as abscisic acid (aba) and jasmonate (ja). some plants can counteract pathogen virulence by invoking a potent form of immunity called effector-triggered immunity (eti). here, we report that aba and ja mediate inactivation of the immune-associated map kinases (mapks), mpk3 and mpk6, in arabidopsis thaliana aba induced expression of genes encoding the protein phosphatases 2c (pp2cs), hai1 ...201728652328
functional characterization of key residues in regulatory proteins hrpg and hrpv of pseudomonas syringae pv. tomato dc3000.the plant pathogen pseudomonas syringae pv. tomato dc3000 uses a type iii secretion system (t3ss) to transfer effector proteins into the host. the expression of t3ss proteins is controlled by the hrpl σ factor. transcription of hrpl is σ(54)-dependent and bacterial enhancer-binding proteins hrpr and hrps coactivate the hrpl promoter. the hrpv protein imposes negative control upon hrpr and hrps through direct interaction with hrps. hrpg interacts with hrpv and relieves such negative control. the ...201728488468
complete sequence and comparative genomic analysis of eight native pseudomonas syringae plasmids belonging to the ppt23a family.the ppt23a family of plasmids appears to be indigenous to the plant pathogen pseudomonas syringae and these plasmids are widely distributed and widely transferred among pathovars of p. syringae and related species. ppt23a-family plasmids (pfps) are sources of accessory genes for their hosts that can include genes important for virulence and epiphytic colonization of plant leaf surfaces. the occurrence of repeated sequences including duplicated insertion sequences on pfps has made obtaining close ...201728486968
Refresh
firstprev
...9192
nextlast
Displaying items 9001 - 9100 of 9107