| characterization of the coronatine-like phytotoxins produced by the common scab pathogen streptomyces scabies. | streptomyces scabies is an important causative agent of common scab disease of potato tubers and other root crops. the primary virulence factor produced by this pathogen is a phytotoxic secondary metabolite called thaxtomin a, which is essential for disease development. in addition, the genome of s. scabies harbors a virulence-associated biosynthetic gene cluster called the coronafacic acid (cfa)-like gene cluster, which was previously predicted to produce metabolites that resemble the pseudomon ... | 2015 | 25423263 |
| downy mildew resistant 6 and dmr6-like oxygenase 1 are partially redundant but distinct suppressors of immunity in arabidopsis. | arabidopsis downy mildew resistant 6 (dmr6) mutants have lost their susceptibility to the downy mildew hyaloperonospora arabidopsidis. here we show that dmr6 is also resistant to the bacterium pseudomonas syringae and the oomycete phytophthora capsici. resistance is accompanied by enhanced defense gene expression and elevated salicylic acid levels. the suppressive effect of the dmr6 oxygenase was confirmed in transgenic arabidopsis lines overexpressing dmr6 that show enhanced susceptibility to h ... | 2015 | 25376907 |
| ald1 regulates basal immune components and early inducible defense responses in arabidopsis. | robust immunity requires basal defense machinery to mediate timely responses and feedback cycles to amplify defenses against potentially spreading infections. agd2-like defense response protein 1 (ald1) is needed for the accumulation of the plant defense signal salicylic acid (sa) during the first hours after infection with the pathogen pseudomonas syringae and is also upregulated by infection and sa. ald1 is an aminotransferase with multiple substrates and products in vitro. pipecolic acid (pip ... | 2015 | 25372120 |
| environmental stresses modulate abundance and timing of alternatively spliced circadian transcripts in arabidopsis. | environmental stresses profoundly altered accumulation of nonsense mrnas including intron retaining (ir) transcripts in arabidopsis. temporal patterns of stress-induced ir mrnas were dissected using both oscillating and non-oscillating transcripts. broad range thermal cycles triggered a sharp increase in the long intron retaining cca1 isoforms and altered their phasing to different times of day. both abiotic and biotic stresses such as drought or p. syringae infection induced similar increase. t ... | 2014 | 25366180 |
| antimicrobial activity of essential oils of thymus vulgaris and origanum vulgare on phytopathogenic strains isolated from soybean. | the aim of this work was to study the antimicrobial activity of essential oils obtained from thymus vulgaris (thyme) and origanum vulgare (oregano) on phytopathogenic pseudomonas species isolated from soybean. strains with characteristics of p. syringae were isolated from leaves of soybean plants with blight symptoms. ten of these could be identified in group ia of lopat as p. syringae. six of these were confirmed as p. syringae using 16s rrna, indicating the presence of these phytopathogenic ba ... | 2015 | 25359697 |
| synthesis and antibacterial activities of yanglingmycin analogues. | the synthesis of yanglingmycin and its enantiomer, along with eighteen yanglingmycin analogues is reported. the structures were confirmed mainly by analyses of nmr spectral data. antibacterial activity assays showed that yanglingmycin and some of its analogues exhibited significant antibacterial activities against two important agricultural pathogenic bacteria, ralstonia solanacearum and pseudomonas syringae pv. actinidiae, with mic values ranging from 3.91 to 15.62 μg/ml. the antibacterial acti ... | 2014 | 25355464 |
| folic acid induces salicylic acid-dependent immunity in arabidopsis and enhances susceptibility to alternaria brassicicola. | folates are essential for one-carbon transfer reactions in all organisms and contribute, for example, to de novo dna synthesis. here, we detected the folate precursors 7,8-dihydropteroate (dhp) and 4-amino-4-deoxychorismate (adc) in extracts from arabidopsis thaliana plants by fourier transform ion cyclotron resonance-mass spectrometry. the accumulation of dhp, but not adc, was induced after infection of plants with pseudomonas syringae delivering the effector protein avrrpm1. application of fol ... | 2015 | 25348251 |
| insect eggs induce a systemic acquired resistance in arabidopsis. | although they constitute an inert stage of the insect's life, eggs trigger plant defences that lead to egg mortality or attraction of egg parasitoids. we recently found that salicylic acid (sa) accumulates in response to oviposition by the large white butterfly pieris brassicae, both in local and systemic leaves, and that plants activate a response that is similar to the recognition of pathogen-associated molecular patterns (pamps), which are involved in pamp-triggered immunity (pti). here we di ... | 2014 | 25329965 |
| activation tagging of athb13 in arabidopsis thaliana confers broad-spectrum disease resistance. | powdery mildew species oidium neolycopersici (on) can cause serious yield losses in tomato production worldwide. besides on tomato, on is able to grow and reproduce on arabidopsis. in this study we screened a collection of activation-tagged arabidopsis mutants and identified one mutant, 3221, which displayed resistance to on, and in addition showed a reduced stature and serrated leaves. additional disease tests demonstrated that the 3221 mutant exhibited resistance to downy mildew (hyaloperonosp ... | 2014 | 25293871 |
| [agrobacterium-mediated transformation of ljamp2 gene into 'red sun' kiwifruit and its molecular identification]. | bacterial canker caused by pseudomonas syringae pv. actinidiae is one of the most important diseases of kiwifruit (actinidia chinensis) and leads to considerable yield losses. in order to obtain transgenic plants with resistance for 'red sun' kiwifruit to canker disease, a non-specific lipid transfer protein-like antimicrobial protein gene (ljamp2) from motherwort (leonurus japonicus) was introduced into 'red sun' kiwifruit through agrobacterium-mediated transformation. after two days of co-cult ... | 2014 | 25212010 |
| ethylene production in relation to nitrogen metabolism in saccharomyces cerevisiae. | we have previously shown that ethylene production in saccharomyces cerevisiae expressing the ethylene-forming enzyme (efe) from pseudomonas syringae is strongly influenced by variations in the mode of cultivation as well as the choice of nitrogen source. here, we have studied the influence of nitrogen metabolism on the production of ethylene further. using ammonium, glutamate, glutamate/arginine, and arginine as nitrogen sources, it was found that glutamate (with or without arginine) correlates ... | 2014 | 25195797 |
| perturbation of bacterial ice nucleation activity by a grass antifreeze protein. | certain plant-associating bacteria produce ice nucleation proteins (inps) which allow the crystallization of water at high subzero temperatures. many of these microbes are considered plant pathogens since the formed ice can damage tissues, allowing access to nutrients. intriguingly, certain plants that host these bacteria synthesize antifreeze proteins (afps). once freezing has occurred, plant afps likely function to inhibit the growth of large damaging ice crystals. however, we postulated that ... | 2014 | 25193694 |
| characterization of quorum sensing-controlled transcriptional regulator marr and rieske (2fe-2s) cluster-containing protein (orf5), which are involved in resistance to environmental stresses in pseudomonas syringae pv. tabaci 6605. | pseudomonas syringae pv. tabaci 6605 (pta6605) produces acyl homoserine lactones (ahls), quorum sensing (qs) molecules that are indispensable for virulence in host tobacco infection. genome-wide transcriptional profiling of several qs-defective mutants revealed that the expression of the genes encoding the marr family transcriptional regulator (marr) and a rieske 2fe-2s cluster-containing protein (orf5) located adjacent to psyi, a gene encoding ahl synthetase, are significantly repressed. exogen ... | 2015 | 25155081 |
| molecular characterization of rice sphingosine-1-phosphate lyase gene osspl1 and functional analysis of its role in disease resistance response. | our results indicate that overexpression of osspl1 in transgenic tobacco plants attenuated disease resistance and facilitated programmed cell death. long-chain base phosphates including sphingosine-1-phosphate have been shown to act as signaling mediators in regulating programmed cell death (pcd) and stress responses in mammals. in the present study, we characterized a rice gene osspl1, encoding a putative sphingosine-1-phosphate lyase that is involved in metabolism of sphingosine-1-phosphate. e ... | 2014 | 25113543 |
| the role of cell wall-based defences in the early restriction of non-pathogenic hrp mutant bacteria in arabidopsis. | we have investigated the cause of the restricted multiplication of hrp mutant bacteria in leaves of arabidopsis. our focus was on early interactions leading to differentiation between virulent wild-type and non-pathogenic hrpa mutant strains of pseudomonas syringae pv. tomato. an initial drop in recoverable bacteria detected 0-4 h after inoculation with either strain was dependent on a functional fls2 receptor and h2o2 accumulation in challenged leaves. wild-type bacteria subsequently multiplied ... | 2015 | 25108744 |
| absence of endo-1,4-β-glucanase kor1 alters the jasmonate-dependent defence response to pseudomonas syringae in arabidopsis. | during plant-pathogen interactions, the plant cell wall forms part of active defence against invaders. in recent years, cell wall-editing enzymes, associated with growth and development, have been related to plant susceptibility or resistance. our previous work identified a role for several tomato and arabidopsis endo-1,4-β-glucanases (egs) in plant-pathogen interactions. here we studied the response of the arabidopsis thaliana t-dna insertion mutant lacking eg korrigan1 (kor1) infected with pse ... | 2014 | 25108263 |
| effect of oxygen on the growth and biofilm formation of xylella fastidiosa in liquid media. | xylella fastidiosa is a xylem-limited bacterial pathogen, and is the causative agent of pierce's disease of grapevines and scorch diseases of many other plant species. the disease symptoms are putatively due to blocking of the transpiration stream by bacterial-induced biofilm formation and/or by the formation of plant-generated tylosis. xylella fastidiosa has been classified as an obligate aerobe, which appears unusual given that dissolved o2 levels in the xylem during the growing season are oft ... | 2014 | 25100224 |
| melatonin as a signal molecule triggering defense responses against pathogen attack in arabidopsis and tobacco. | melatonin plays pleiotropic roles in both animals and plants. the possible role of melatonin in plant innate immune responses was recently discovered. as an initial study, we employed arabidopsis to determine whether melatonin is involved in defense against the virulent bacterial pathogen pseudomonas syringae dc3000. the application of a 10 μm concentration of melatonin on arabidopsis and tobacco leaves induced various pathogenesis-related (pr) genes, as well as a series of defense genes activat ... | 2014 | 25099383 |
| phenotypic analyses of arabidopsis t-dna insertion lines and expression profiling reveal that multiple l-type lectin receptor kinases are involved in plant immunity. | l-type lectin receptor kinases (lecrk) are membrane-spanning receptor-like kinases with putative roles in biotic and abiotic stress responses and in plant development. in arabidopsis, 45 lecrk were identified but their functions are largely unknown. here, a systematic functional analysis was carried out by evaluating phenotypic changes of arabidopsis lecrk t-dna insertion lines in plant development and upon exposure to various external stimuli. none of the lecrk t-dna insertion lines showed clea ... | 2014 | 25083911 |
| manipulation of mks1 gene expression affects kalanchoë blossfeldiana and petunia hybrida phenotypes. | the establishment of alternative methods to chemical treatments for growth retardation and pathogen protection in ornamental plant production has become a major goal in recent breeding programmes. this study evaluates the effect of manipulating map kinase 4 nuclear substrate 1 (mks1) expression in kalanchoë blossfeldiana and petunia hybrida. the arabidopsis thaliana mks1 gene was overexpressed in both species via agrobacterium-mediated transformation, resulting in dwarfed phenotypes and delayed ... | 2015 | 25082411 |
| the circadian clock and defence signalling in plants. | the circadian clock is the internal time-keeping machinery in higher organisms. cross-talk between the circadian clock and a diverse range of physiological processes in plants, including stress acclimatization, hormone signalling, photomorphogenesis and defence signalling, is currently being explored. recent studies on circadian clock genes and genes involved in defence signalling have indicated a possible reciprocal interaction between the two. it has been proposed that the circadian clock shap ... | 2015 | 25081907 |
| a prominent role for rcar3-mediated aba signaling in response to pseudomonas syringae pv. tomato dc3000 infection in arabidopsis. | in plant-pathogen interaction, the plant hormone aba can serve as a crucial modulator of plant responses to biotic as well as abiotic stress. recent studies have identified pyrabactin resistance (pyr) 1/pyr1-like (pyl)/regulatory component of aba receptor (rcar) proteins as an aba receptor that interacts with the protein phosphatase type 2c (pp2c) family. here, we examined the functional involvement of aba signaling components in pre- and post-invasive defense responses of arabidopsis against th ... | 2014 | 25063782 |
| change in activity of serine palmitoyltransferase affects sensitivity to syringomycin e in yeast saccharomyces cerevisiae. | syringomycin e is a cyclic lipodepsipeptide produced by strains of the plant bacterium pseudomonas syringae pv. syringae. genetic studies involving the yeast saccharomyces cerevisiae have revealed that complex sphingolipids play important roles in the action of syringomycin e. here, we found a novel mutation that confers resistance to syringomycin e on yeast; that is, a deletion mutant of orm1 and orm2, which encode negative regulators of serine palmitoyltransferase catalyzing the initial step o ... | 2014 | 25040056 |
| constitutive camalexin production and environmental stress response variation in arabidopsis populations from the iberian peninsula. | optimal defense theory predicts that induction of defensive secondary metabolites in plants will be inversely correlated with constitutive expression of those compounds. here, we asked whether camalexin, an important defense against fungal and bacterial pathogens, support this prediction in structured natural populations of arabidopsis thaliana from the iberian peninsula. in common garden experiments, we found that genotypes from the vie population constitutively hyper-accumulated camalexin. cam ... | 2014 | 25017162 |
| rice saps are responsive to multiple biotic stresses and overexpression of ossap1, an a20/an1 zinc-finger protein, enhances the basal resistance against pathogen infection in tobacco. | eukaryotic a20/an1 zinc-finger proteins (zfps) play an important role in the regulation of immune and stress response. after elucidation of the role of first such protein, ossap1, in abiotic stress tolerance, 18 rice stress associated protein (sap) genes have been shown to be regulated by multiple abiotic stresses. in the present study, expression pattern of all the 18 ossap genes have been analysed in response to different biotic stress simulators, in order to get insights into their possible i ... | 2014 | 25017161 |
| transgenic tomato plants overexpressing tyramine n-hydroxycinnamoyltransferase exhibit elevated hydroxycinnamic acid amide levels and enhanced resistance to pseudomonas syringae. | 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 tom ... | 2014 | 25014592 |
| rational design of a ligand-based antagonist of jasmonate perception. | (+)-7-iso-jasmonoyl-l-isoleucine (ja-ile) regulates developmental and stress responses in plants. its perception involves the formation of a ternary complex with the f-box coi1 and a member of the jaz family of co-repressors and leads to jaz degradation. coronatine (cor) is a bacterial phytotoxin that functionally mimics ja-ile and interacts with the coi1-jaz co-receptor with higher affinity than ja-ile. on the basis of the co-receptor structure, we designed ligand derivatives that spatially imp ... | 2014 | 24997606 |
| a framework to gauge the epidemic potential of plant pathogens in environmental reservoirs: the example of kiwifruit canker. | new economically important diseases on crops and forest trees emerge recurrently. an understanding of where new pathogenic lines come from and how they evolve is fundamental for the deployment of accurate surveillance methods. we used kiwifruit bacterial canker as a model to assess the importance of potential reservoirs of new pathogenic lineages. the current kiwifruit canker epidemic is at least the fourth outbreak of the disease on kiwifruit caused by pseudomonas syringae in the mere 50 years ... | 2015 | 24986268 |
| differential control of pre-invasive and post-invasive antibacterial defense by the arabidopsis circadian clock. | plants show a suite of inducible defense responses against bacterial pathogens. here we investigate in detail the effect of the circadian clock on these reactions in arabidopsis thaliana. the magnitude of immune responses elicited by flg22, by virulent and by avirulent pseudomonas syringae strains depends on the time of day of inoculation. the oxidative burst is stronger when flg22 is infiltrated in the morning in wild-type plants but not in the arrhythmic clock mutant lux arrhythmo/phytoclock1 ... | 2014 | 24974385 |
| abscisic acid-cytokinin antagonism modulates resistance against pseudomonas syringae in tobacco. | 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 oth ... | 2014 | 24941328 |
| altered growth and improved resistance of arabidopsis against pseudomonas syringae by overexpression of the basic amino acid transporter atcat1. | amino acid transporters in plants are crucial for distributing amino acids between plant organs and cellular compartments. the h(+)-coupled plasma membrane transporter cat1 (cationic amino acid transporter 1) facilitates the high-affinity uptake of basic amino acids. the uptake of lysine (lys) via the roots was not altered in loss-of-function mutants, in accordance with the minor expression of cat1 in roots, but plants ectopically overexpressing cat1 incorporated lys at higher rates. exogenous l ... | 2014 | 24895758 |
| role of the penetration-resistance genes pen1, pen2 and pen3 in the hypersensitive response and race-specific resistance in arabidopsis thaliana. | plants are highly capable of recognizing and defending themselves against invading microbes. adapted plant pathogens secrete effector molecules to suppress the host's immune system. these molecules may be recognized by host-encoded resistance proteins, which then trigger defense in the form of the hypersensitive response (hr) leading to programmed cell death of the host tissue at the infection site. the three proteins pen1, pen2 and pen3 have been found to act as central components in cell wall- ... | 2014 | 24889055 |
| definition of plant-pathogenic pseudomonas genomospecies of the pseudomonas syringae complex through multiple comparative approaches. | a total of 34 phytopathogenic strain genomes belonging to the pseudomonas syringae species complex and related species, including many pathotype strains, were assessed using average nucleotide identity (ani) analysis. their taxonomic relationships were consistently confirmed by the tetranucleotide frequency correlation coefficient (tetra) values, multilocus sequence typing analysis (mlsa) performed with seven housekeeping genes, using both maximum likelihood and bayesian methods, and split conse ... | 2014 | 24875383 |
| intercellular salicylic acid accumulation during compatible and incompatible arabidopsis-pseudomonas syringae interactions. | the phytohormone salicylic acid (sa) plays an important role in several disease resistance responses. during the age-related resistance (arr) response that occurs in mature arabidopsis responding to pseudomonas syringae pv tomato (pst), sa accumulates in the intercellular space where it may act as an antimicrobial agent. recently we measured intracellular and intercellular sa levels in young, arr-incompetent plants responding to virulent and avirulent strains of pst to determine if intercellular ... | 2014 | 24874267 |
| spatial and temporal dynamics of primary and secondary metabolism in phaseolus vulgaris challenged by pseudomonas syringae. | 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 ther ... | 2015 | 24871330 |
| order of arrival shifts endophyte-pathogen interactions in bean from resistance induction to disease facilitation. | endophytic fungi colonize plants without causing symptoms of disease and can enhance the resistance of their host to pathogens. we cultivated 53 fungal strains from wild lima bean (phaseolus lunatus) and investigated their effects on pathogens using in vitro assays and experiments in planta. most strains were annotated as rhizopus, fusarium, penicillium, cochliobolus, and artomyces spp. by the sequence of their 18s rrna gene. in vitro confrontation assays between endophytes and three pathogens ( ... | 2014 | 24801140 |
| bigger is not always better: transmission and fitness burden of ∼1mb pseudomonas syringae megaplasmid pmppla107. | 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 ... | 2014 | 24792221 |
| constitutive salicylic acid accumulation in pi4kiiiβ1β2 arabidopsis plants stunts rosette but not root growth. | phospholipids have recently been found to be integral elements of hormone signalling pathways. an arabidopsis thaliana double mutant in two type iii phosphatidylinositol-4-kinases (pi4ks), pi4kiiiβ1β2, displays a stunted rosette growth. the causal link between pi4k activity and growth is unknown. using microarray analysis, quantitative reverse transcription polymerase chain reaction (rt-qpcr) and multiple phytohormone analysis by lc-ms we investigated the mechanism responsible for the pi4kiiiβ1β ... | 2014 | 24758581 |
| the arabidopsis immune adaptor srfr1 interacts with tcp transcription factors that redundantly contribute to effector-triggered immunity. | the plant immune system must be tightly controlled both positively and negatively to maintain normal plant growth and health. we previously identified suppressor of rps4-rld1 (srfr1) as a negative regulator specifically of effector-triggered immunity. srfr1 is localized in both a cytoplasmic microsomal compartment and in the nucleus. its tpr domain has sequence similarity to tpr domains of transcriptional repressors in other organisms, suggesting that srfr1 may negatively regulate effector-trigg ... | 2014 | 24689742 |
| applicability of preparative overpressured layer chromatography and direct bioautography in search of antibacterial chamomile compounds. | in situ sample preparation and preparative overpressured layer chromatography (oplc) fractionation on a 0.5 mm thick adsorbent layer of chamomile flower methanol extract prepurified by conventional gravitation accelerated column chromatography were applied in searching for bioactive components. sample cleanup in situ on the adsorbent layer subsequent to sample application was performed using mobile phase flow in the opposite direction (the input and output of the eluent was exchanged). the antib ... | 2014 | 24645496 |
| dige-abpp by click chemistry: pairwise comparison of serine hydrolase activities from the apoplast of infected plants. | activity-based protein profiling (abpp) is a targeted functional proteomics method that displays the active proteome by using small molecule probes that react covalently with the active sites of protein classes. comparison of activity profiles from two different samples is not always easy, especially when using probes that generate too many signals. for accurate comparison of protein activities between two proteomes, we developed difference gel electrophoresis abpp (dige-abpp), which compares tw ... | 2014 | 24643562 |
| a bacterial tyrosine phosphatase inhibits plant pattern recognition receptor activation. | innate immunity relies on the perception of pathogen-associated molecular patterns (pamps) by pattern-recognition receptors (prrs) located on the host cell's surface. many plant prrs are kinases. here, we report that the arabidopsis receptor kinase ef-tu receptor (efr), which perceives the elf18 peptide derived from bacterial elongation factor tu, is activated upon ligand binding by phosphorylation on its tyrosine residues. phosphorylation of a single tyrosine residue, y836, is required for acti ... | 2014 | 24625928 |
| hopz4 from pseudomonas syringae, a member of the hopz type iii effector family from the yopj superfamily, inhibits the proteasome in plants. | the yopj family of type iii effector proteins (t3e) is one of the largest and most widely distributed families of effector proteins, whose members are highly diversified in virulence functions. in the present study, hopz4, a member of the yopj family of t3e from the cucumber pathogen pseudomonas syringae pv. lachrymans is described. hopz4 shares high sequence similarity with the xanthomonas t3e xopj, and a functional analysis suggests a conserved virulence function between these two t3e. as has ... | 2014 | 24625030 |
| the performance of pathogenic bacterial phytosensing transgenic tobacco in the field. | phytosensors are useful for rapid-on-the-plant detection of contaminants and agents that cause plant stress. previously, we produced a series of plant pathogen-inducible synthetic promoters fused to an orange fluorescent protein (ofp) reporter gene and transformed them into tobacco and arabidopsis thaliana plants; in these transgenic lines, an ofp signal is expressed commensurate with the presence of plant pathogens. we report here the results of 2 years of field experiments using a subset of th ... | 2014 | 24618221 |
| the arabidopsis thaliana at4g13040 gene, a unique member of the ap2/erebp family, is a positive regulator for salicylic acid accumulation and basal defense against bacterial pathogens. | the arabidopsis genome contains a large number of putative transcription factors, containing a dna binding domain similar to apetala2/ethylene response element binding protein (ap2/erebp), for most of which a function is not known. phylogenetic analysis divides the apetala 2 (ap2) super-family into 5 major groups: ap2, rav, ethylene response factor (erf), dehydration response element binding protein (dreb) and at4g13040. similar to erf and dreb, the at4g13040 protein contains only one ap2 domain ... | 2014 | 24612849 |
| the pseudomonas viridiflava phylogroups in the p. syringae species complex are characterized by genetic variability and phenotypic plasticity of pathogenicity-related traits. | as a species complex, pseudomonas syringae exists in both agriculture and natural aquatic habitats. p.viridiflava, a member of this complex, has been reported to be phenotypically largely homogenous. we characterized strains from different habitats, selected based on their genetic similarity to previously described p.viridiflava strains. we revealed two distinct phylogroups and two different kinds of variability in phenotypic traits and genomic content. the strains exhibited phase variation in p ... | 2014 | 24612372 |
| reversible non-genetic phenotypic heterogeneity in bacterial quorum sensing. | bacteria co-ordinate their social behaviour in a density-dependent manner by production of diffusible signal molecules by a process known as quorum sensing (qs). it is generally assumed that in homogenous environments and at high cell density, qs synchronizes cells in the population to perform collective social tasks in unison which maximize the benefit at the inclusive fitness of individuals. however, evolutionary theory predicts that maintaining phenotypic heterogeneity in performing social ta ... | 2014 | 24601980 |
| analysis of the small rna spf in the plant pathogen pseudomonas syringae pv. tomato strain dc3000. | bacteria contain small non-coding rnas (ncrnas) that are typically responsible for altering transcription, translation or mrna stability. ncrnas are important because they often regulate virulence factors and susceptibility to various stresses. here, the regulation of a recently described ncrna of pseudomonas syringae dc3000, spot 42 (now referred to as spf), was investigated. a putative rpoe binding site was identified upstream of spf in strain dc3000. rpoe is shown to regulate the expression o ... | 2014 | 24600027 |
| the hygroscopic biosurfactant syringafactin produced by pseudomonas syringae enhances fitness on leaf surfaces during fluctuating humidity. | biosurfactant production by bacteria on leaf surfaces is poorly documented, and its role in this habitat has not been explored. therefore, we investigated the production and fitness benefits of syringafactin by pseudomonas syringae pv. syringae b728a on leaves. syringafactin largely adsorbed to the waxy leaf cuticle both when topically applied and when produced by cells on plants. syringafactin increased the rate of diffusion of water across isolated cuticles and attracted water to hydrophobic s ... | 2014 | 24571678 |
| recte(psy)-mediated recombineering in pseudomonas syringae. | a recently developed pseudomonas syringae recombineering system simplifies the procedure for installing specific mutations at a chosen genomic locus. the procedure involves transforming p. syringae cells expressing recombineering functions with a pcr product that contains desired changes flanked by sequences homologous to a target location. cells transformed with the substrate undergo homologous recombination between the genomic dna and the recombineering substrate. the recombinants are found by ... | 2014 | 24557893 |
| proteomic analysis of the actinidia deliciosa leaf apoplast during biotrophic colonization by pseudomonas syringae pv. actinidiae. | for plant pathogenic bacteria, adaptation to the apoplast is considered as key in the establishment of the parasitic lifestyle. pseudomonas syringae pv. actinidiae (psa), the causal agent of the bacterial canker of kiwifruit, uses leaves as the entry site to colonize plants. through a combined approach based on 2-de, nanolc-esi-lit-ms/ms and quantitative pcr, we investigated psa colonization of the actinidia deliciosa "hayward" leaf apoplast during the bacterial biotrophic phase. a total of 58 d ... | 2014 | 24530627 |
| regulation of plant immunity through ubiquitin-mediated modulation of ca(2+) -calmodulin-atsr1/camta3 signaling. | transient changes in intracellular ca(2+) concentration are essential signals for activation of plant immunity. it has also been reported that ca(2+) signals suppress salicylic acid-mediated plant defense through atsr1/camta3, a member of the ca(2+) /calmodulin-regulated transcription factor family that is conserved in multicellular eukaryotes. how plants overcome this negative regulation to mount an effective defense response during a stage of intracellular ca(2+) surge is unclear. here we repo ... | 2014 | 24528504 |
| backbone and stereospecific (13)c methyl ile (δ1), leu and val side-chain chemical shift assignments of crc. | carbon catabolite repression (ccr) allows bacteria to selectively assimilate a preferred compound among a mixture of several potential carbon sources, thus boosting growth and economizing the cost of adaptability to variable nutrients in the environment. the rna-binding catabolite repression control (crc) protein acts as a global post-transcriptional regulator of ccr in pseudomonas species. crc triggers repression by inhibiting the expression of genes involved in transport and catabolism of non- ... | 2015 | 24496608 |
| the impact of cytokinin on jasmonate-salicylate antagonism in arabidopsis immunity against infection with pst dc3000. | cytokinin has long been shown to be an essential modulator of growth and development in plants. however, its implications in plant immunity have only recently been realized. the interaction between jasmonate and salicylate pathways is regarded as a central backbone of plant immune defense. however, the effect of cytokinin on the jasmonate and salicylate mediated balance in plant immunity is still not known. here, we analyze the impact of cytokinin on the jasmonate-salicylate antagonism in arabid ... | 2013 | 24494231 |
| [production of inhibiting plant growth and development hormones by pathogenic for legumes pseudomonas genus bacteria]. | it has been studied the ability of pathogenic for legumes pathovars of pseudomonas genus to produce ethylene and abscisic acid in vitro. a direct correlation between the level of ethylene production by agent of bacterial pea burn--pseudomonas syringae pv. pisi and level of its aggressiveness for plants has been found. it is shown that the amount of abscisic acid synthesized by pathogenic for legumes pseudomonas genus bacteria correlates with their aggressiveness for plants. | 2014 | 24450185 |
| genome sequence and comparative genome analysis of pseudomonas syringae pv. syringae type strain atcc 19310. | pseudomonas syringae pv. syringae (psy) is a major bacterial pathogen of many economically important plant species. despite the severity of its impact, the genome sequence of the type strain has not been reported. here, we present the draft genome sequence of psy atcc 19310. comparative genomic analysis revealed that psy atcc 19310 is closely related to psy b728a. however, only a few type iii effectors, which are key virulence factors, are shared by the two strains, indicating the possibility of ... | 2014 | 24444998 |
| characterization of three arabidopsis thaliana immunophilin genes involved in the plant defense response against pseudomonas syringae. | plant immunophilins are a broadly conserved family of proteins, which carry out a variety of cellular functions. in this study, we investigated three immunophilin genes involved in the arabidopsis thaliana response to pseudomonas syringae infection: a cytoplasmic localized atcyp19, a cytoplasmic and nuclear localized atcyp57, and one nucleus directed fkbp known as atfkbp65. arabidopsis knock-out mutations in these immunophilins result in an increased susceptibility to p. syringae, whereas overex ... | 2014 | 24440291 |
| molecular characterization and functional analysis of outer membrane vesicles from the antarctic bacterium pseudomonas syringae suggest a possible response to environmental conditions. | outer membrane vesicles (omvs) of gram-negative bacteria form an important aspect of bacterial physiology as they are involved in various functions essential for their survival. the omvs of the antarctic bacterium pseudomonas syringae lz4w were isolated, and the proteins and lipids they contain were identified. the matrix-assisted laser desorption/ionization time of flight (maldi-tof/tof) analysis revealed that phosphatidylethanolamines and phosphatidylglycerols are the main lipid components. th ... | 2014 | 24437924 |
| determination of the self-association residues within a homomeric and a heteromeric aaa+ enhancer binding protein. | the σ(54)-dependent transcription in bacteria requires specific activator proteins, bacterial enhancer binding protein (bebp), members of the aaa+ (atpases associated with various cellular activities) protein family. the bebps usually form oligomers in order to hydrolyze atp and make open promoter complexes. the bebp formed by hrpr and hrps activates transcription from the σ(54)-dependent hrpl promoter responsible for triggering the type three secretion system in pseudomonas syringae pathovars. ... | 2014 | 24434682 |
| bioprecipitation: a feedback cycle linking earth history, ecosystem dynamics and land use through biological ice nucleators in the atmosphere. | landscapes influence precipitation via the water vapor and energy fluxes they generate. biologically active landscapes also generate aerosols containing microorganisms, some being capable of catalyzing ice formation and crystal growth in clouds at temperatures near 0 °c. the resulting precipitation is beneficial for the growth of plants and microorganisms. mounting evidence from observations and numerical simulations support the plausibility of a bioprecipitation feedback cycle involving vegetat ... | 2014 | 24399753 |
| soybean ndr1-like proteins bind pathogen effectors and regulate resistance signaling. | nonrace specific disease resistance 1 (ndr1) is a conserved downstream regulator of resistance (r) protein-derived signaling. we identified two ndr1-like sequences (gmndr1a, b) from soybean, and investigated their roles in r-mediated resistance and pathogen effector detection. silencing gmndr1a and b in soybean shows that these genes are required for resistance derived from the rpg1-b, rpg3, and rpg4 loci, against pseudomonas syringae (psg) expressing avrb, avrb2 and avrd1, respectively. immunop ... | 2014 | 24372490 |
| the bacterial effector hopm1 suppresses pamp-triggered oxidative burst and stomatal immunity. | successful pathogens counter immunity at multiple levels, mostly through the action of effectors. pseudomonas syringae secretes c. 30 effectors, some of which have been shown to inhibit plant immunity triggered upon perception of conserved pathogen-associated molecular patterns (pamps). one of these is hopm1, which impairs late immune responses through targeting the vesicle trafficking-related atmin7 for degradation. here, we report that in planta expressed hopm1 suppresses two early pamp-trigge ... | 2014 | 24372399 |
| a new feature selection method for computational prediction of type iii secreted effectors. | the type iii secretion system (t3ss) is a specialised protein delivery system that plays an important role in pathogenic bacteria. however, the secretion mechanism has not been fully understood yet. especially, the identification of type iii secreted effectors is a notoriously challenging problem which has attracted a lot of research interests in recent years. in this paper, we introduce a machine learning method using amino acid sequence features for predicting t3ses. we use a topic model calle ... | 2014 | 25946888 |
| characterization of a tryptophan 2-monooxygenase gene from puccinia graminis f. sp. tritici involved in auxin biosynthesis and rust pathogenicity. | the plant hormone indole-3-acetic acid (iaa) is best known as a regulator of plant growth and development but its production can also affect plant-microbe interactions. microorganisms, including numerous plant-associated bacteria and several fungi, are also capable of producing iaa. the stem rust fungus puccinia graminis f. sp. tritici induced wheat plants to accumulate auxin in infected leaf tissue. a gene (pgt-iaam) encoding a putative tryptophan 2-monooxygenase, which makes the auxin precurso ... | 2014 | 24350783 |
| heat shock protein 70 is required for tabtoxinine-β-lactam-induced cell death in nicotiana benthamiana. | tabtoxinine-β-lactam (tβl), a non-specific bacterial toxin, is produced by pseudomonas syringae pv. tabaci, the causal agent of tobacco wildfire disease. tβl causes death of plant cells through the inhibition of glutamine synthetase, which leads to an abnormal accumulation of ammonium ions and the characteristic necrotic wildfire lesions. to better understand the mechanisms involved in tβl-induced cell death, we studied its regulation in nicotiana benthamiana. tβl-induced lesions, similar to tho ... | 2014 | 24331433 |
| the pseudomonas syringae type iii effector hopd1 suppresses effector-triggered immunity, localizes to the endoplasmic reticulum, and targets the arabidopsis transcription factor ntl9. | • pseudomonas syringae type iii effectors are known to suppress plant immunity to promote bacterial virulence. however, the activities and targets of these effectors are not well understood. • we used genetic, molecular, and cell biology methods to characterize the activities, localization, and target of the hopd1 type iii effector in arabidopsis. • hopd1 contributes to p. syringae virulence in arabidopsis and reduces effector-triggered immunity (eti) responses but not pathogen-associated molecu ... | 2014 | 24329768 |
| pathogenesis-related protein 4b interacts with leucine-rich repeat protein 1 to suppress pr4b-triggered cell death and defense response in pepper. | to control defense and cell-death signaling, plants contain an abundance of pathogen recognition receptors such as leucine-rich repeat (lrr) proteins. here we show that pepper (capsicum annuum) lrr1 interacts with the pepper pathogenesis-related (pr) protein 4b, pr4b, in yeast and in planta. pr4b is synthesized in the endoplasmic reticulum, interacts with lrr1 in the plasma membrane, and is secreted to the apoplast via the plasma membrane. binding of pr4b to lrr1 requires the chitin-binding doma ... | 2014 | 24304389 |
| distinct pseudomonas type-iii effectors use a cleavable transit peptide to target chloroplasts. | the pathogen pseudomonas syringae requires a type-iii protein secretion system and the effector proteins it injects into plant cells for pathogenesis. the primary role for p. syringae type-iii effectors is the suppression of plant immunity. the p. syringae pv. tomato dc3000 hopk1 type-iii effector was known to suppress the hypersensitive response (hr), a programmed cell death response associated with effector-triggered immunity. here we show that dc3000 hopk1 mutants are reduced in their ability ... | 2014 | 24299018 |
| ectopic expression of zmsimk1 leads to improved drought tolerance and activation of systematic acquired resistance in transgenic tobacco. | the mitogen-activated protein kinase (mapk) cascades play pivotal roles in diverse signaling pathways related to plant biotic and abiotic stress responses. in this study, a group b mapk gene in zea mays, zmsimk1, was functionally analyzed. quantitative real-time pcr (qrt-pcr) analysis indicated that zmsimk1 transcript could be induced by drought, salt, pseudomonas syringae pv. tomato dc3000 (pst dc3000) and certain exogenous signaling molecules. analysis of the zmsimk1 promoter revealed a group ... | 2014 | 24291188 |
| the arabidopsis tandem zinc finger 9 protein binds rna and mediates pathogen-associated molecular pattern-triggered immune responses. | recognition of pathogen-associated molecular patterns (pamps) induces multiple defense mechanisms to limit pathogen growth. here, we show that the arabidopsis thaliana tandem zinc finger protein 9 (tzf9) is phosphorylated by pamp-responsive mitogen-activated protein kinases (mapks) and is required to trigger a full pamp-triggered immune response. analysis of a tzf9 mutant revealed attenuation in specific pamp-triggered reactions such as reactive oxygen species accumulation, mapk activation and, ... | 2014 | 24285750 |
| validation of real-time pcr assays for bioforensic detection of model plant pathogens. | the u.s. agricultural sector is vulnerable to intentionally introduced microbial threats because of its wide and open distribution and economic importance. to investigate such events, forensically valid assays for plant pathogen detection are needed. in this work, real-time pcr assays were developed for three model plant pathogens: pseudomonas syringae pathovar tomato, xylella fastidiosa, and wheat streak mosaic virus. validation included determination of the linearity and range, limit of detect ... | 2014 | 24261870 |
| plant flavonoids target pseudomonas syringae pv. tomato dc3000 flagella and type iii secretion system. | 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 co ... | 2013 | 24249293 |
| incongruence between multi-locus sequence analysis (mlsa) and whole-genome-based phylogenies: pseudomonas syringae pathovar pisi as a cautionary tale. | previous phylogenies, built using a subset of genomic loci, split pseudomonas syringae pv. pisi into two well-supported clades and implied convergence in host range for these lineages. the analysis of phenotypic and genotypic data within the context of this phylogenetic relationship implied further convergence at the level of virulence gene loss and acquisition. we generate draft genome assemblies for two additional p. syringae strains, isolated from diseased pea plants, and demonstrate incongru ... | 2014 | 24224664 |
| arabidopsis cysteine-rich receptor-like kinase 45 positively regulates disease resistance to pseudomonas syringae. | arabidopsis cysteine-rich receptor-like protein kinase 45 (crk45) was found to be involved in aba signaling in arabidopsis thaliana previously. here, we reported that it also positively regulates disease resistance. the crk45 overexpression plants increased expression of the defense genes, and enhanced resistance to pseudomonas syringae whereas the crk45 mutant were more sensitive to p. syringae and weakened expression of the defense genes, compared to the wild type. we also found that treatment ... | 2013 | 24215930 |
| overexpression of constitutively active oscpk10 increases arabidopsis resistance against pseudomonas syringae pv. tomato and rice resistance against magnaporthe grisea. | calcium-dependent protein kinases (cdpks) are crucial calcium sensors involved in plant responses to pathogen infection. here, we report isolation and functional characterization of the pathogen-responsive rice oscpk10 gene. the expression of oscpk10 was strongly induced following treatment with a magnaporthe grisea elicitor. kinase activity assay showed that the functional oscpk10 protein not only autophosphorylated, but also phosphorylated casein in a calcium-dependent manner. overexpression o ... | 2013 | 24141028 |
| microwave assisted synthesis, antifungal activity and dft theoretical study of some novel 1,2,4-triazole derivatives containing the 1,2,3-thiadiazole moiety. | in order to investigate the biological activity of 1,2,4-triazole compounds, seventeen novel 1,2,4-triazole derivatives containing 1,2,3-thiadiazole moieties were synthesized by multi-step reactions under microwave assisted conditions. the structures were characterized by 1h-nmr, 13c-nmr, ms and elemental analyses. the target compounds were evaluated for their in vivo fungicidal activities against corynespora cassiicola, pseudomonas syringae pv. lachrymans, and pseudoperonospora cubensis, and th ... | 2013 | 24132196 |
| phytotoxins produced by plant pathogenic streptomyces species. | streptomyces is a large genus consisting of soil-dwelling, filamentous bacteria that are best known for their capability of producing a vast array of medically and agriculturally useful secondary metabolites. in addition, a small number of streptomyces spp. are capable of colonizing and infecting the underground portions of living plants and causing economically important crop diseases such as potato common scab (cs). research into the mechanisms of streptomyces plant pathogenicity has led to th ... | 2014 | 24131731 |
| the secondary metabolism glycosyltransferases ugt73b3 and ugt73b5 are components of redox status in resistance of arabidopsis to pseudomonas syringae pv. tomato. | secondary metabolism plant glycosyltransferases (ugts) ensure conjugation of sugar moieties to secondary metabolites (sms) and glycosylation contributes to the great diversity, reactivity and regulation of sms. ugt73b3 and ugt73b5, two ugts of arabidopsis thaliana (arabidopsis), are involved in the hypersensitive response (hr) to the avirulent bacteria pseudomonas syringae pv. tomato (pst-avrrpm1), but their function in planta is unknown. here, we report that ugt73b3, ugt73b5 and ugt73b3 ugt73b5 ... | 2014 | 24131360 |
| the pseudomonas type iii effector hopq1 activates cytokinin signaling and interferes with plant innate immunity. | we characterized the molecular function of the pseudomonas syringae pv. tomato dc3000 (pto) effector hopq1. in silico studies suggest that hopq1 might possess nucleoside hydrolase activity based on the presence of a characteristic aspartate motif. transgenic arabidopsis lines expressing hopq1 or hopq1 aspartate mutant variants were characterized with respect to flagellin triggered immunity, phenotype and changes in phytohormone content by high-performance liquid chromatography-ms (hplc-ms). we f ... | 2014 | 24124900 |
| soil water flow is a source of the plant pathogen pseudomonas syringae in subalpine headwaters. | 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.syr ... | 2014 | 24118699 |
| a pseudomonas syringae diversity survey reveals a differentiated phylotype of the pathovar syringae associated with the mango host and mangotoxin production. | pseudomonas syringae pv. syringae, the causal agent of bacterial apical necrosis (ban) in mango crops, has been isolated in different mango-producing areas worldwide. an extensive collection of 87 p. syringae pv. syringae strains isolated from mango trees affected by ban from different countries, but mainly from southern spain, were initially examined by repetitive sequence-based polymerase chain reaction (rep-pcr) to analyze the genetic diversity with an epidemiological aim. rep-pcr was powerfu ... | 2013 | 24102210 |
| the pepper patatin-like phospholipase caplp1 functions in plant cell death and defense signaling. | phospholipases hydrolyze phospholipids into fatty acids and other lipophilic substances. phospholipid signaling is crucial for diverse cellular processes in plants. however, the precise role of phospholipases in plant cell death and defense signaling is not fully understood. here, we identified a pepper (capsicum annuum) patatin-like phospholipase (caplp1) gene that is transcriptionally induced in pepper leaves by avirulent xanthomonas campestris pv. vesicatoria (xcv) infection. caplp1 containin ... | 2014 | 24085708 |
| thermally stable harpin, hrpzpss is sensitive to chemical denaturants: probing tryptophan environment, chemical and thermal unfolding by fluorescence spectroscopy. | harpins - a group of proteins that elicit hypersensitive response (hr) in non-host plants - are secreted by certain gram-negative plant pathogenic bacteria upon interaction with the plant. in the present study, the microenvironment and solvent accessibility of the sole tryptophan residue (trp-167) in harpin hrpzpss, secreted by pseudomonas syringae pv. syringae, have been characterized by fluorescence spectroscopic studies. emission λmax of the native protein at 328 nm indicates that trp-167 is ... | 2013 | 24055159 |
| the tomato kinome and the tomato kinase library orfeome: novel resources for the study of kinases and signal transduction in tomato and solanaceae species. | protein kinase-driven phosphorylation constitutes the core of cellular signaling. kinase components of signal transduction pathways are often targeted for inactivation by pathogens. the study of kinases and immune signal transduction in the model crop tomato (solanum lycopersicum) would benefit from the availability of community-wide resources for large scale and systems-level experimentation. here, we defined the tomato kinome and performed a comprehensive comparative analysis of the tomato kin ... | 2014 | 24047240 |
| light regulates motility, attachment and virulence in the plant pathogen pseudomonas syringae pv tomato dc3000. | pseudomonas syringae pv tomato dc3000 (pto) is the causal agent of the bacterial speck of tomato, which leads to significant economic losses in this crop. pto inhabits the tomato phyllosphere, where the pathogen is highly exposed to light, among other environmental factors. light represents a stressful condition and acts as a source of information associated with different plant defence levels. here, we analysed the presence of both blue and red light photoreceptors in a group of pseudomonas. in ... | 2014 | 24033935 |
| a salicylic acid-induced lectin-like protein plays a positive role in the effector-triggered immunity response of arabidopsis thaliana to pseudomonas syringae avr-rpm1. | salicylic acid (sa) is one of the key hormones that orchestrate the pathogen-induced immune response in plants. this response is often characterized by the activation of a local hypersensitive reaction involving programmed cell death, which constrains proliferation of biotrophic pathogens. here, we report the identification and functional characterization of an sa-induced legume lectin-like protein 1 (sai-llp1), which is coded by a gene that belongs to the group of early sa-activated arabidopsis ... | 2013 | 24006883 |
| [pseudomonas syringae - the agent of bacterial diseases of weeds]. | the symptoms of bacterial diseases of the associated weeds have been identified and described in the wheat crops grown in different farming systems. on the basis of its morphological, biochemical and serological properties the agent isolated from frost-blite, barnyard grass, wild radish, couch grass, bottle-brush, bindweed and sow thistle has been identified as pseudomonas syringae. serological affinity between the weed bacteria and the agent of bacterial diseases of cereals has been established ... | 2013 | 24006783 |
| salicylic acid-dependent and -independent impact of an rna-binding protein on plant immunity. | plants overexpressing the rna-binding protein atgrp7 (atgrp7-ox plants) constitutively express the pr-1 (pathogenesis-related-1), pr-2 and pr-5 transcripts associated with salicylic acid (sa)-mediated immunity and show enhanced resistance against pseudomonas syringae pv. tomato (pto) dc3000. here, we investigated whether the function of atgrp7 in plant immunity depends on sa. endogenous sa was elevated fivefold in atgrp7-ox plants. the elevated pr-1, pr-2 and pr-5 levels were eliminated upon exp ... | 2014 | 23961939 |
| a novel role of pr2 in abscisic acid (aba) mediated, pathogen-induced callose deposition in arabidopsis thaliana. | pathogenesis-related protein 2 (pr2) is known to play a major role in plant defense and general stress responses. resistance against the fungal pathogen leptosphaeria maculans in arabidopsis requires abscisic acid (aba), which promotes the deposition of callose, a β-1,3-glucan polymer. here, we examined the role of pr2 in callose deposition in relation to aba treatment and challenge with l. maculans and pseudomonas syringae. characterization of pr2-overexpressing plants and the knockout line ind ... | 2013 | 23952213 |
| arabidopsis yellow stripe-like7 (ysl7) and ysl8 transporters mediate uptake of pseudomonas virulence factor syringolin a into plant cells. | syringolin a (syla), a virulence factor secreted by certain strains of the plant pathogen pseudomonas syringae pv. syringae, is an irreversible proteasome inhibitor imported by plant cells by an unknown transport process. here, we report that functional expression in yeast of all 17 members of the arabidopsis oligopeptide transporter family revealed that oligopeptide transporter1 (opt1), opt2, yellow stripe-like3 (ysl3), ysl7, and ysl8 rendered yeast cells sensitive to growth inhibition by syla ... | 2013 | 23945001 |
| pcr amplification of the hrcv gene through specific primers for detecting pseudomonas syringae pathovars. | pseudomonas syringae pathovars are important pathogens among phytopathogenic bacteria causing a variety of diseases in plants. these pathogens can rapidly disseminate in a large area leading to infection and destruction of plants. to prevent the incidence of the bacteria, appropriate detection methods should be employed. routinely serological tests, being time-consuming and costly, are exploited to detect these pathogens in plants, soil, water and other resources. over the recent years, dna-base ... | 2014 | 23933804 |
| the chinese wild grapevine (vitis pseudoreticulata) e3 ubiquitin ligase erysiphe necator-induced ring finger protein 1 (eirp1) activates plant defense responses by inducing proteolysis of the vpwrky11 transcription factor. | ubiquitin-mediated regulation responds rapidly to specific stimuli; this rapidity is particularly important for defense responses to pathogen attack. here, we investigated the role of the e3 ubiquitin ligase erysiphe necator-induced ring finger protein 1 (eirp1) in the defense response of chinese wild grapevine vitis pseudoreticulata. the regulatory function of e3 ubiquitin ligase eirp1 was investigated using molecular, genetic and biochemical approaches. eirp1 encodes a c3hc4-type really intere ... | 2013 | 23905547 |
| in planta induced changes in the native plasmid profile of pseudomonas syringae pathover phaseolicola strain 1302a. | pseudomonas syringae pv. phaseolicola (pph) strain 1302a, a causative agent of halo blight in the common bean phaseolus vulgaris, contains four native plasmids designated pav505 (150 kb), pav506 (50 kb), pav507 (47 kb) and pav508 (42 kb). pph 1302a also contains a 106 kb genomic island pphgi-1 which shares features with integrative and conjugative elements (icelands) and carries the effector gene avrpphb (hopar1) which triggers a defensive response in bean cultivars carrying the matching r3 resi ... | 2013 | 23895800 |
| phosphatidylcholine synthesis is essential for hrpz harpin secretion in plant pathogenic pseudomonas syringae and non-pathogenic pseudomonas sp. 593. | 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 ... | 2014 | 23886927 |
| lov-domain photoreceptor, encoded in a genomic island, attenuates the virulence of pseudomonas syringae in light-exposed arabidopsis leaves. | in arabidopsis thaliana, light signals modulate the defences against bacteria. here we show that light perceived by the lov domain-regulated two-component system (pst-lov) of pseudomonas syringae pv. tomato dc3000 (pst dc3000) modulates virulence against a. thaliana. bioinformatic analysis and the existence of an episomal circular intermediate indicate that the locus encoding pst-lov is present in an active genomic island acquired by horizontal transfer. strains mutated at pst-lov showed enhance ... | 2013 | 23865633 |
| salicyloyl-aspartate synthesized by the acetyl-amido synthetase gh3.5 is a potential activator of plant immunity in arabidopsis. | salicylic acid (sa) plays a critical role in plant immunity responses against pathogen infection, especially in the establishment of systemic acquired resistance. whether other forms of salicylates also function in plant immunity has not been explored. our previous study has revealed that salicyloyl-aspartate (sa-asp), the only reported endogenous sa-amino acid conjugate in plants, was highly accumulated in the arabidopsis activation-tagged mutant gh3.5-1d after pathogen infection. in this study ... | 2013 | 23842113 |
| replication arrest is a major threat to growth at low temperature in antarctic pseudomonas syringae lz4w. | chromosomal damage was detected previously in the recbcd mutants of the antarctic bacterium pseudomonas syringae lz4w, which accumulated linear chromosomal dna leading to cell death and growth inhibition at 4°c. recbcd protein generally repairs dna double-strand breaks by reca-dependent homologous recombination pathway. here we show that δreca mutant of p. syringae is not cold-sensitive. significantly, inactivation of additional dna repair genes ruvab rescued the cold-sensitive phenotype of δrec ... | 2013 | 23815755 |
| induction and suppression of pen3 focal accumulation during pseudomonas syringae pv. tomato dc3000 infection of arabidopsis. | the pleiotropic drug resistance (pdr) proteins belong to the super-family of atp-binding cassette (abc) transporters. atpdr8, also called pen3, is required for penetration resistance of arabidopsis to nonadapted powdery mildew fungi. during fungal infection, plasma-membrane-localized pen3 is concentrated at fungal entry sites, as part of the plant's focal immune response. here, we show that the pen3 mutant is compromised in resistance to the bacterial pathogen pseudomonas syringae pv. tomato dc3 ... | 2013 | 23815470 |
| the phtl protein of pseudomonas syringae pv. phaseolicola nps3121 affects the expression of both phaseolotoxin cluster (pht) and non-pht encoded genes. | pseudomonas syringae pv. phaseolicola, the causal agent of halo blight disease in bean, produces a toxin known as phaseolotoxin, whose synthesis involves the products of some of the genes found within the pht region. this region, considered a pathogenicity island, comprises 23 genes arranged in five transcriptional units: two single-gene units (argk, phtl) and three arranged as operons (phta, phtd, phtm), most with unknown function. in p. syringae pv. phaseolicola, maximal expression of most of ... | 2014 | 23806843 |
| the widespread plant-colonizing bacterial species pseudomonas syringae detects and exploits an extracellular pool of choline in hosts. | the quaternary ammonium compound (qac) choline is a major component of membrane lipids in eukaryotes and, if available to microbial colonists of plants, could provide benefits for growth and protection from stress. free choline is found in homogenized plant tissues, but its subcellular location and availability to plant microbes are not known. whole-cell bacterial bioreporters of the phytopathogen pseudomonas syringae were constructed that couple a qac-responsive transcriptional fusion with well ... | 2013 | 23763788 |