Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
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| genetics of bacterial alginate: alginate genes distribution, organization and biosynthesis in bacteria. | bacterial alginate genes are chromosomal and fairly widespread among rrna homology group i pseudomonads and azotobacter. in both genera, the genetic pathway of alginate biosynthesis is mostly similar and the identified genes are identically organized into biosynthetic, regulatory and genetic switching clusters. in spite of these similarities,still there are transcriptional and functional variations between p. aeruginosa and a. vinelandii. in p. aeruginosa all biosynthetic genes except algc trans ... | 2007 | 18645604 |
| bacterial non-host resistance: interactions of arabidopsis with non-adapted pseudomonas syringae strains. | although interactions of plants with virulent and avirulent host pathogens are under intensive study, relatively little is known about plant interactions with non-adapted pathogens and the molecular events underlying non-host resistance. here we show that two pseudomonas syringae strains for which arabidopsis is a non-host plant, p. syringae pathovar (pv.) glycinea (psg) and p. syringae pv. phaseolicola (psp),induce salicylic acid (sa) accumulation and pathogenesis-related gene expression at ino ... | 2007 | 18251883 |
| characterization of antimicrobial compounds produced by pseudomonas aurantiaca s-1. | pseudomonas aurantiaca s-1 can serve as a natural source of pesticides towards phytopathogens like fusarium oxysporum p1 and pseudomonas syringae pv. glycinea bim b-280. the largest pool of produced antimicrobial compounds was found in four days-old spent culture supernatant. at least two groups of bioactive substances were identified, one responsible for the antibacterial activity and the other for the antifungal activity. the fraction with strong antibacterial activity had the molecular mass 2 ... | 2007 | 18254494 |
| [antimicrobial activity of calendula l. plants]. | the sap of different organs of genus calendula plant species has been studied for antimicrobial activity. the sap of racemes demonstrated the most expressed antimicrobial effect while that of the roots - the least one. calendula species inhibited all tested pathogenic microorganisms, especially pseudomonas syringae, p. fluorescens, xanthomonas campestris, agrobacterium tumefaciens. calendula suffruticosa was the most active to all investigated microorganisms. | 2007 | 18217350 |
| the complete genome sequence and analysis of the epsilonproteobacterium arcobacter butzleri. | arcobacter butzleri is a member of the epsilon subdivision of the proteobacteria and a close taxonomic relative of established pathogens, such as campylobacter jejuni and helicobacter pylori. here we present the complete genome sequence of the human clinical isolate, a. butzleri strain rm4018. | 2007 | 18159241 |
| rar1 and hsp90 form a complex with rac/rop gtpase and function in innate-immune responses in rice. | a rice (oryza sativa) rac/rop gtpase, os rac1, is involved in innate immunity, but its molecular function is largely unknown. rar1 (for required for mla12 resistance) and hsp90 (a heat shock protein 90 kd) are important components of r gene-mediated disease resistance, and their function is conserved in several plant species. hsp90 has also recently been shown to be important in mammalian innate immunity. however, their functions at the molecular level are not well understood. in this study, we ... | 2007 | 18156216 |
| natural variation in rps2-mediated resistance among arabidopsis accessions: correlation between gene expression profiles and phenotypic responses. | natural variation in gene expression (expression traits or e-traits) is increasingly used for the discovery of genes controlling traits. an important question is whether a particular e-trait is correlated with a phenotypic trait. here, we examined the correlations between phenotypic traits and e-traits among 10 arabidopsis thaliana accessions. we studied defense against pseudomonas syringae pv tomato dc3000 (pst), with a focus on resistance gene-mediated resistance triggered by the type iii effe ... | 2007 | 18083910 |
| modulation of bacterial type iii secretion system by a spermidine transporter dependent signaling pathway. | many gram-negative bacterial pathogens employ type iii secretion systems (t3ss) to inject effector proteins into host cells in infectious processes. | 2007 | 18074016 |
| temporal gene expression profiling of the wheat leaf rust pathosystem using cdna microarray reveals differences in compatible and incompatible defence pathways. | in this study, we detail the construction of a custom cdna spotted microarray containing 7728 wheat ests and the use of the array to identify host genes that are differentially expressed upon challenges with leaf rust fungal pathogens. wheat cultivar rl6003 (thatcher lr1) was inoculated with puccinia triticina virulence phenotypes bbb (incompatible) or tjb (7-2) (compatible) and sampled at four different time points (3, 6, 12, and 24 hours) after inoculation. transcript expression levels relativ ... | 2007 | 18288238 |
| [composition, structure, and biological properties of lipopolysaccharides from different strains of pseudomonas syringae pv. atrofaciens]. | the composition, structure, and certain biological properties of lipopolysaccharides (lps) isolated from six strains of bacteria pseudomonas syringae pv. atrofaciens pathogenic for grain-crops (wheat, rye) are presented. the lps-protein complexes were isolated by a sparing procedure (extraction from microbial cells with a weak salt solution). they reacted with the homologous o sera and contained one to three antigenic determinants. against the cells of warm-blooded animals (mice, humans) they ex ... | 2007 | 18297868 |
| the downy mildew effector proteins atr1 and atr13 promote disease susceptibility in arabidopsis thaliana. | the downy mildew (hyaloperonospora parasitica) effector proteins atr1 and atr13 trigger rpp1-nd/wsb- and rpp13-nd-dependent resistance, respectively, in arabidopsis thaliana. to better understand the functions of these effectors during compatible and incompatible interactions of h. parasitica isolates on arabidopsis accessions, we developed a novel delivery system using pseudomonas syringae type iii secretion via fusions of atrs to the n terminus of the p. syringae effector protein, avrrps4. atr ... | 2007 | 18165328 |
| expression of a ring-hc protein from rice improves resistance to pseudomonas syringae pv. tomato dc3000 in transgenic arabidopsis thaliana. | a cdna clone (osrhc1) was obtained, which encodes a novel ring zinc finger protein sharing similar structural features (multiple transmembrane domains at the n-half; a unique ring zinc finger consensus cys-x(2)-cys-x(11)-cys-x-his-x(3)-cys-x(2)-cys-x(6)-cys-x(2)-cys at the c terminus) to a group of closely related annotated proteins from both monocots and dicots. osrhc1 was found to be localized on plasma membrane of rice cells and induced by wounding in rice lines containing xa loci. ecotopic e ... | 2007 | 18182423 |
| using pseudomonas spp. for integrated biological control. | abstract pseudomonas spp. have been studied for decades as model organisms for biological control of plant disease. currently, there are three commercial formulations of pseudomonads registered with the u.s. environmental protection agency for plant disease suppression, bio-save 10 lp, bio-save 11 lp, and blightban a506. bio-save 10 lp and bio-save 11 lp, products of jet harvest solutions, longwood, fl, contain pseudomonas syringae strains esc-10 and esc-11, respectively. these products are appl ... | 2007 | 18944382 |
| systemic acquired resistance in canola is linked with pathogenesis-related gene expression and requires salicylic acid. | abstract systemic acquired resistance (sar) is an induced defense response that confers long-lasting protection against a broad range of microbial pathogens. here we show that treatment of brassica napus plants with the sar-inducing chemical benzo-(1,2,3)-thiadiazole-7-carbothioic acid s-methyl ester (bth) significantly enhanced resistance against virulent strains of the bacterial pathogen pseudomonas syringae pv. maculicola and the fungal pathogen leptosphaeria maculans. localized preinoculatio ... | 2007 | 18943928 |
| the phytotoxin coronatine from pseudomonas syringae pv. tomato dc3000 functions as a virulence factor and influences defence pathways in edible brassicas. | summary the phytotoxin coronatine (cor) contributes to the virulence of pseudomonas syringae pv. tomato (pst) strain dc3000 on arabidopsis thaliana and tomato. however, little is known regarding the role of cor in the virulence of dc3000 on cultivated brassica spp. in this study, the role of cor and its precursors, coronafacic acid (cfa) and coronamic acid (cma), were examined in the virulence of pst dc3000 on collard and turnip, two important edible brassicas. pst dc3000 and three well-defined ... | 2007 | 20507480 |
| disease resistance to bacterial pathogens affected by the amount of ferredoxin-i protein in plants. | summary ferredoxin-i (fd-i) is a fundamental protein that is involved in several metabolic pathways. the amount of fd-i found in plants is generally regulated by environmental stress, including biotic and abiotic events. in this study, the correlation between quantity of fd-i and plant disease resistance was investigated. fd-i levels were increased by inoculation with pseudomonas syringae pv. syringae but were reduced by erwinia carotovora ssp. carotovora. transgenic tobacco over-expressing fd-i ... | 2007 | 20507485 |
| the tobacco ntann12 gene, encoding an annexin, is induced upon rhodoccocus fascians infection and during leafy gall development. | summary annexins are calcium-binding proteins that have been associated in plants with different biological processes such as responses to abiotic stress and early nodulation stages. until now, the implication of annexins during plant-pathogen interactions has not been reported. here, a novel plant annexin gene induced in tobacco by-2 cell suspension cultures infected with the phytopathogenic bacterium rhodococcus fascians (strain d188) has been identified. expression of this gene, called ntann1 ... | 2007 | 20507490 |
| dspa/e, a type iii effector of erwinia amylovora, is required for early rapid growth in nicotiana benthamiana and causes nbsgt1-dependent cell death. | summary dspa/e is a pathogenicity factor of erwinia amylovora that is translocated into the plant cell cytoplasm through an hrp type iii secretion system. transient expression of dspa/e in nicotiana benthamiana or yeast induced cell death, as it does in n. tabacum and apple as described previously. dspa/e-induced cell death in n. benthamiana was not inhibited by coexpression of avrptob of pseudomonas syringae pv. tomato, which inhibits programmed cell death (pcd) induced by several other elicito ... | 2007 | 20507497 |
| competitive index in mixed infections: a sensitive and accurate assay for the genetic analysis of pseudomonas syringae-plant interactions. | summary: mixed infections have been broadly applied to the study of bacterial pathogens in animals. however, the application of mixed infection-based methods in plant pathogens has been very limited. an important factor for this limitation is the different dynamics that mixed infections have been reported to show in the different types of models. reports in systemic animal infections have shown that any bacterium has the same probability of multiplying within a mixed infection than in a single i ... | 2007 | 20507512 |
| the leucine-rich repeat (lrr) protein, calrr1, interacts with the hypersensitive induced reaction (hir) protein, cahir1, and suppresses cell death induced by the cahir1 protein. | summary: leucine-rich repeat proteins (lrrs) function in a number of signal transduction pathways via protein-protein interactions. the gene encoding a small protein of pepper, calrr1, is specifically induced upon pathogen challenge and treatment with pathogen-associated molecular patterns (pamps). we identified a pepper hypersensitive induced reaction (cahir1) protein that interacts with the lrr domain of the calrr1 protein using yeast two-hybrid screening. ectopic expression of the pepper cahi ... | 2007 | 20507517 |
| the 18mer peptaibols from trichoderma virens elicit plant defence responses. | summary peptaibols, the products of non-ribosomal peptide synthetases (nrps), are linear peptide antibiotics produced by trichoderma and other fungal genera. trichoderma virens strain gv29-8, a well-known biocontrol agent and inducer of plant defence responses, produces three lengths of peptaibols, 11, 14 and 18 residues long, with several isoforms of each. disruption of the nrps gene, tex1, encoded by a 62.8-kb uninterrupted open reading frame, results in the loss of production of all forms of ... | 2007 | 20507534 |
| disturbance of the ca(2+)/calmodulin-dependent signalling pathway is responsible for the resistance of arabidopsis dnd1 against pectobacterium carotovorum infection. | summary arabidopsis thaliana wild-type col-0 and its mutant, 'defence, no death' (dnd) 1-1, were infected with biotrophic pseudomonas syringae pv. tomato strain dc3000 and necrotrophic pectobacterium carotovorum strain kacc 10228, and cellular and molecular responses among them were then analysed. col-0 wild-type was susceptible to both pathogens. by contrast, neither dc3000 nor kacc 10228 infected dnd1-1 (yu et al., 1998. proc. natl. acad. sci. usa 95: 7819-7824). neither of the pathogens trigg ... | 2007 | 20507535 |
| interaction between sgt1 and cytosolic/nuclear hsc70 chaperones regulates arabidopsis immune responses. | the conserved eukaryotic protein sgt1 (for suppressor of g2 allele of skp1) has characteristics of an hsp90 (for heat shock protein 90 kd) cochaperone and in plants regulates hormone responses and resistance gene-triggered immunity. we affinity-purified sgt1-interacting proteins from arabidopsis thaliana leaf extracts and identified by mass spectrometry cytosolic heat shock cognate 70 (hsc70) chaperones as the major stable sgt1 interactors. arabidopsis sgt1a and sgt1b proteins associate with hsc ... | 2007 | 18065690 |
| pseudomonas syringae type iii effector avrrpt2 alters arabidopsis thaliana auxin physiology. | the pseudomonas syringae type iii effector avrrpt2 promotes bacterial virulence on arabidopsis thaliana plants lacking a functional rps2 gene (rps2 mutant plants). to investigate the mechanisms underlying the virulence activity of avrrpt2, we examined the phenotypes of transgenic a. thaliana rps2 seedlings constitutively expressing avrrpt2. these seedlings exhibited phenotypes reminiscent of a. thaliana mutants with altered auxin physiology, including longer primary roots, increased number of la ... | 2007 | 18056646 |
| bioinformatic evaluation of l-arginine catabolic pathways in 24 cyanobacteria and transcriptional analysis of genes encoding enzymes of l-arginine catabolism in the cyanobacterium synechocystis sp. pcc 6803. | so far very limited knowledge exists on l-arginine catabolism in cyanobacteria, although six major l-arginine-degrading pathways have been described for prokaryotes. thus, we have performed a bioinformatic analysis of possible l-arginine-degrading pathways in cyanobacteria. further, we chose synechocystis sp. pcc 6803 for a more detailed bioinformatic analysis and for validation of the bioinformatic predictions on l-arginine catabolism with a transcript analysis. | 2007 | 18045455 |
| ectopic expression of apple mbr7 gene induced enhanced resistance to transgenic arabidopsis plant against a virulent pathogen. | a disease resistance related gene, mbr7, was identified in the wild apple species, malus baccata. the mbr7 gene has a single open reading frame (orf) of 3,288 nucleotides potentially encoding a 1,095-amino acid protein. its deduced amino acid sequence resembles the n protein of tobacco and the nl27 gene of potato and has several motifs characteristic of a tir-nbs-lrr r gene subclass. ectopic expression of mbr7 in arabidopsis enhanced the resistance against a virulent pathogen, pseudomonas syring ... | 2007 | 18051364 |
| a two-strain mixture of rhizobacteria elicits induction of systemic resistance against pseudomonas syringae and cucumber mosaic virus coupled to promotion of plant growth on arabidopsis thaliana. | we evaluated a commercial biopreparation of plant growth-promoting rhizobacteria (pgpr) strains bacillus subtilis gb03 and b. amyloliquefaciens in937a formulated with the carrier chitosan (bioyield) for its capacity to elicit growth promotion and induced systemic resistance against infection by cucumber mosaic virus (cmv) and pseudomonas syringae pv. tomato dc3000 in arabidopsis thaliana. the biopreparation promoted plant growth of arabidopsis hormonal mutants, which included auxin, gibberellic ... | 2007 | 18051759 |
| preliminary investigations on inducing salt tolerance in maize through inoculation with rhizobacteria containing acc deaminase activity. | twenty rhizobacterial strains containing 1-aminocyclopropane-1-carboxylate deaminase were isolated from the rhizosphere of salt-affected maize fields. they were screened for their growth-promoting activities under axenic conditions at 1, 4, 8, and 12 ds x m-1 salinity levels. based upon the data of the axenic study, the 6 most effective strains were selected to conduct pot trials in the wire house. besides one original salinity level (1.6 ds x m-1), 3 other salinity levels (4, 8, and 12 ds x m-1 ... | 2007 | 18026206 |
| identification of prophages in bacterial genomes by dinucleotide relative abundance difference. | prophages are integrated viral forms in bacterial genomes that have been found to contribute to interstrain genetic variability. many virulence-associated genes are reported to be prophage encoded. present computational methods to detect prophages are either by identifying possible essential proteins such as integrases or by an extension of this technique, which involves identifying a region containing proteins similar to those occurring in prophages. these methods suffer due to the problem of l ... | 2007 | 18030328 |
| a pseudomonas syringae effector inactivates mapks to suppress pamp-induced immunity in plants. | pathogen-associated molecular patterns (pamps) elicit basal defense responses in plants, and, in turn, pathogens have evolved mechanisms to overcome these pamp-induced defenses. to suppress immunity, the phytopathogenic bacterium pseudomonas syringae secretes effector proteins, the biochemical function and virulence targets of which remain largely unknown. we show that hopai1, an effector widely conserved in both plant and animal bacterial pathogens, inhibits the arabidopsis mitogen-activated pr ... | 2007 | 18005697 |
| a novel class of bacteria-induced small rnas in arabidopsis. | small rnas, including micrornas (mirnas) and small interfering rnas (sirnas), are essential regulatory molecules of many cellular processes. arabidopsis has at least three classes of endogenous sirnas--chromatin-associated sirnas, trans-acting sirnas (tasirnas), and natural antisense transcript (nat)-associated sirnas (nat-sirnas)--all 20-25 nucleotides (nt) in length. here, we identified a novel class of small rnas, long sirnas (lsirnas), which are 30-40 nt and share many common features with k ... | 2007 | 18003861 |
| the developmental selector as1 is an evolutionarily conserved regulator of the plant immune response. | the myb-related gene asymmetric leaves 1 (as1) and its orthologs have an evolutionarily conserved role in specification of leaf cell identity. as1 is expressed in leaf founder cells, where it functions as a heterodimer with the structurally unrelated as2 proteins to repress activity of knotted 1-like homeobox (knox) genes. as1 therefore confines knox activity to the shoot apical meristem, where it promotes stem cell function through the regulation of phytohormone activities. here, we show that l ... | 2007 | 18003921 |
| a photosensory two-component system regulates bacterial cell attachment. | flavin-binding lov domains are blue-light photosensory modules that are conserved in a number of developmental and circadian regulatory proteins in plants, algae, and fungi. lov domains are also present in bacterial genomes, and are commonly located at the amino termini of sensor histidine kinases. genes predicted to encode lov-histidine kinases are conserved across a broad range of bacterial taxa, from aquatic oligotrophs to plant and mammalian pathogens. however, the function of these putative ... | 2007 | 17986614 |
| brucella suis urease encoded by ure1 but not ure2 is necessary for intestinal infection of balb/c mice. | in prokaryotes, the ureases are multi-subunit, nickel-containing enzymes that catalyze the hydrolysis of urea to carbon dioxide and ammonia. the brucella genomes contain two urease operons designated as ure1 and ure2. we investigated the role of the two brucella suis urease operons on the infection, intracellular persistence, growth, and resistance to low-ph killing. | 2007 | 17578575 |
| argonaute4 is required for resistance to pseudomonas syringae in arabidopsis. | here, we report the characterization of the arabidopsis thaliana ocp11 (for overexpressor of cationic peroxidase11) mutant, in which a beta-glucuronidase reporter gene under the control of the h(2)o(2)-responsive ep5c promoter is constitutively expressed. ocp11 plants show enhanced disease susceptibility to the virulent bacterium pseudomonas syringae pv tomato dc3000 (p.s.t. dc3000) and also to the avirulent p.s.t. dc3000 carrying the effector avrrpm1 gene. in addition, ocp11 plants are also com ... | 2007 | 17993621 |
| separation of plant pathogens from different hosts and tissues by capillary electromigration techniques. | in this contribution capillary isoelectric focusing and capillary zone electrophoresis were applied for the separation and detection of different plant pathogens including pseudomonas syringae pv. syringae, p. syringae pv. lachrymans, pseudomonas savastanoi pv. fraxinus, p. savastanoi pv. olea, agrobacterium tumefaciens, a vitis, xanthomonas arboricola pv. juglandis, x. campestris pv. zinniae, and curtobacterium sp.. the uv detection and sensitive fluorescence detection of the native phytopathog ... | 2007 | 17997525 |
| regulation of tradeoffs between plant defenses against pathogens with different lifestyles. | plants activate distinct defense responses depending on the lifestyle of the attacker encountered. in these responses, salicylic acid (sa) and jasmonic acid (ja) play important signaling roles. sa induces defense against biotrophic pathogens that feed and reproduce on live host cells, whereas ja activates defense against necrotrophic pathogens that kill host cells for nutrition and reproduction. cross-talk between these defense signaling pathways has been shown to optimize the response against a ... | 2007 | 17998535 |
| comparative genomic analysis of two-component regulatory proteins in pseudomonas syringae. | pseudomonas syringae is a widespread bacterial plant pathogen, and strains of p. syringae may be assigned to different pathovars based on host specificity among different plant species. the genomes of p. syringae pv. syringae (psy) b728a, pv. tomato (pto) dc3000 and pv. phaseolicola (pph) 1448a have been recently sequenced providing a major resource for comparative genomic analysis. a mechanism commonly found in bacteria for signal transduction is the two-component system (tcs), which typically ... | 2007 | 17971244 |
| sensitivity and speed of induced defense of cabbage (brassica oleracea l.): dynamics of bolox expression patterns during insect and pathogen attack. | the lipoxygenase pathway is involved in the early steps of plant responses to herbivorous insects and phytopathogens. induced defenses in the crucifer brassica oleracea have been well documented. here, we have cloned a lipoxygenase (lox) from b. oleracea (bolox). the sequence reveals that the bolox protein has a transit peptide for chloroplast targeting, which is characteristic for class 2 loxs involved in jasmonic acid (ja) biosynthesis which takes place in the chloroplast. phylogenetic analysi ... | 2007 | 17977145 |
| basal resistance against pseudomonas syringae in arabidopsis involves wrky53 and a protein with homology to a nematode resistance protein. | basal resistance is the ultimately unsuccessful plant defense response to infection with a virulent pathogen. it is thought to be triggered by host recognition of pathogen-associated molecular patterns, with subsequent suppression of particular components by pathogen effectors. to identify novel components of arabidopsis basal resistance against the bacterial pathogen pseudomonas syringae pv. tomato, microarray expression profiling was carried out on the cirl mutant, which displays enhanced resi ... | 2007 | 17977154 |
| induction of p-coumaroyldopamine and feruloyldopamine, two novel metabolites, in tomato by the bacterial pathogen pseudomonas syringae. | inoculation of tomato plants (solanum lycopersicum cv. rutgers) with pseudomonas syringae pv. tomato led to the production of a hypersensitive-like response in this pathovar of tomato. accumulation of hydroxycinnamic acid amides (hcaa) of tyramine (p-coumaroyltyramine and feruloyltyramine) and dopamine (p-coumaroyldopamine and feruloyldopamine) was detected after bacterial infection. two of them, p-coumaroyldopamine and feruloyldopamine, are described for the first time. the accumulation of hcaa ... | 2007 | 17977155 |
| a library of linear undecapeptides with bactericidal activity against phytopathogenic bacteria. | a 125-member library of synthetic linear undecapeptides was prepared based on a previously described peptide h-k(1)klfkkilkf(10)l-nh(2) (bp76) that inhibited in vitro growth of the plant pathogenic bacteria erwinia amylovora, xanthomonas axonopodis pv. vesicatoria, and pseudomonas syringae pv. syringae at low micromolar concentrations. peptides were designed using a combinatorial chemistry approach by incorporating amino acids possessing various degrees of hydrophobicity and hydrophilicity at po ... | 2007 | 17980935 |
| novel candidate virulence factors in rice pathogen xanthomonas oryzae pv. oryzicola as revealed by mutational analysis. | bacterial leaf streak, caused by xanthomonas oryzae pv. oryzicola, is an important disease of rice. transposon-mediated mutational analysis of the pathogen with a quantitative assay revealed candidate virulence factors including genes involved in the pathogenesis of other phytopathogenic bacteria, virulence factors of animal pathogens, and genes not previously associated with virulence. | 2007 | 17981946 |
| burkholderia cenocepacia c5424 produces a pigment with antioxidant properties using a homogentisate intermediate. | burkholderia cenocepacia is a gram-negative opportunistic pathogen that belongs to the burkholderia cepacia complex. b. cenocepacia can survive intracellularly within phagocytic cells, and some epidemic strains produce a brown melanin-like pigment that can scavenge free radicals, resulting in the attenuation of the host cell oxidative burst. in this work, we demonstrate that the brown pigment produced by b. cenocepacia c5424 is synthesized from a homogentisate (hga) precursor. the disruption of ... | 2007 | 17933889 |
| the arabidopsis mitogen-activated protein kinase kinase mkk3 is upstream of group c mitogen-activated protein kinases and participates in pathogen signaling. | although the arabidopsis thaliana genome contains genes encoding 20 mitogen-activated protein kinases (mapks) and 10 mapk kinases (mapkks), most of them are still functionally uncharacterized. in this work, we analyzed the function of the group b mapk kinase, mkk3. transgenic promkk3:gus lines showed basal expression in vascular tissues that was strongly induced by pseudomonas syringae pv tomato strain dc3000 (pst dc3000) infection but not by abiotic stresses. the growth of virulent pst dc3000 w ... | 2007 | 17933903 |
| anti-ice nucleation activity in xylem extracts from trees that contain deep supercooling xylem parenchyma cells. | boreal hardwood species, including japanese white birch (betula platyphylla sukat. var. japonica hara), japanese chestnut (castanea crenata sieb. et zucc.), katsura tree (cercidiphyllum japonicum sieb. et zucc.), siebold's beech (fagus crenata blume), mulberry (morus bombycis koidz.), and japanese rowan (sorbus commixta hedl.), had xylem parenchyma cells (xpcs) that adapt to subfreezing temperatures by deep supercooling. crude extracts from xylem in all these trees were found to have anti-ice nu ... | 2007 | 17936742 |
| cloning and characterization of the biosynthetic gene cluster for kutznerides. | kutznerides, actinomycete-derived cyclic depsipetides, consist of six nonproteinogenic residues, including a highly oxygenated tricyclic hexahydropyrroloindole, a chlorinated piperazic acid, 2-(1-methylcyclopropyl)-glycine, a beta-branched-hydroxy acid, and 3-hydroxy glutamic acid, for which biosynthetic logic has not been elucidated. herein we describe the biosynthetic gene cluster for the kutzneride family, identified by degenerate primer pcr for halogenating enzymes postulated to be involved ... | 2007 | 17940045 |
| alternative splicing and mrna levels of the disease resistance gene rps4 are induced during defense responses. | the arabidopsis (arabidopsis thaliana) disease resistance protein resistance to pseudomonas syringae4 (rps4) activates defenses in response to bacterial pathogens expressing avrrps4 in a gene-for-gene specific manner. the rps4 gene produces multiple transcripts via alternative splicing of two regular introns flanking exon 3 and a cryptic intron within exon 3. we showed previously that rps4-mediated resistance requires the combined presence of transcripts encoding both full-length and truncated o ... | 2007 | 17951452 |
| oxo-phytodienoic acid-containing galactolipids in arabidopsis: jasmonate signaling dependence. | the jasmonate family of phytohormones, as represented by 12-oxo-phytodienoic acid (opda), dinor-phytodienoic acid (dn-opda), and jasmonic acid in arabidopsis (arabidopsis thaliana), has been implicated in a vast array of different developmental processes and stress responses. recent reports indicate that opda and dn-opda occur not only as free acids in arabidopsis, but also as esters with complex lipids, so-called arabidopsides. recently, we showed that recognition of the two bacterial effector ... | 2007 | 17951463 |
| the plant growth-promoting fungus penicillium simplicissimum gp17-2 induces resistance in arabidopsis thaliana by activation of multiple defense signals. | arabidopsis thaliana grown in soil amended with barley grain inocula of penicillium simplicissimum gp17-2 or receiving root treatment with its culture filtrate (cf) exhibited clear resistance to pseudomonas syringae pv. tomato dc3000 (pst). to assess the contribution of different defense pathways, arabidopsis genotypes implicated in salicylic acid (sa) signaling expressing the nahg transgene or carrying disruption in npr1 (npr1), jasmonic acid (ja) signaling (jar1) and ethylene (et) signaling (e ... | 2007 | 17956859 |
| functional analysis of polyphenol oxidases by antisense/sense technology. | polyphenol oxidases (ppos) catalyze the oxidation of phenolics to quinones, the secondary reactions of which lead to oxidative browning and postharvest losses of many fruits and vegetables. ppos are ubiquitous in angiosperms, are inducible by both biotic and abiotic stresses, and have been implicated in several physiological processes including plant defense against pathogens and insects, the mehler reaction, photoreduction of molecular oxygen by psi, regulation of plastidic oxygen levels, auron ... | 2007 | 17960074 |
| induction of a small heat shock protein and its functional roles in nicotiana plants in the defense response against ralstonia solanacearum. | in tobacco (nicotiana tabacum), ralstonia solanacearum oe1-1 (rsoe1-1) is pathogenic, whereas r. solanacearum 8107 (rs8107) is nonpathogenic and induces the hypersensitive response (hr). to elucidate the molecular mechanisms of plant-r. solanacearum interactions, we used differential display to isolate a cdna fragment, a6, regulated in tobacco by inoculation with rsoe1-1. the deduced amino acid sequence predicted from full-length a6-cdna showed similarity to small heat shock proteins from arabid ... | 2007 | 17965181 |
| novel hexamerization motif is discovered in a conserved cytoplasmic protein from salmonella typhimurium. | the cytoplasmic protein stm3548 of unknown function obtained from a strain of salmonella typhimurium was determined by x-ray crystallography at a resolution of 2.25 a. the asymmetric unit contains a hexamer of structurally identical monomers. the monomer is a globular domain with a long beta-hairpin protrusion that distinguishes this structure. this beta-hairpin occupies a central position in the hexamer, and its residues participate in the majority of interactions between subunits of the hexame ... | 2007 | 17968677 |
| hydrogen peroxide generation by the pepper extracellular peroxidase capo2 activates local and systemic cell death and defense response to bacterial pathogens. | reactive oxygen species (ros) are responsible for mediating cellular defense responses in plants. controversy has existed over the origin of ros in plant defense. we have isolated a novel extracellular peroxidase gene, capo2, from pepper (capsicum annuum). local or systemic expression of capo2 is induced in pepper by avirulent xanthomonas campestris pv vesicatoria (xcv) infection. we examined the function of the capo2 gene in plant defense using the virus-induced gene silencing technique and gai ... | 2007 | 17905862 |
| linear osmoregulated periplasmic glucans are encoded by the opggh locus of pseudomonas aeruginosa. | osmoregulated periplasmic glucans (opgs) are produced by many proteobacteria and are important for bacterial-host interactions. the opgg and opgh genes involved in the synthesis of opgs are the most widely distributed genes in proteobacterial genomes. two other non-homologous genes, both named ndvb, are also involved in opg biosynthesis in several species. the pseudomonas aeruginosa genome possesses two orfs, pa5077 and pa5078, that show similarity to opgh and opgg of pseudomonas syringae, respe ... | 2007 | 17906125 |
| overexpression of arabidopsis map kinase kinase 7 leads to activation of plant basal and systemic acquired resistance. | there is a growing body of evidence indicating that mitogen-activated protein kinase (mapk) cascades are involved in plant defense responses. analysis of the completed arabidopsis thaliana genome sequence has revealed the existence of 20 mapks, 10 mapkks and 60 mapkkks, implying a high level of complexity in mapk signaling pathways, and making the assignment of gene functions difficult. the map kinase kinase 7 (mkk7) gene of arabidopsis has previously been shown to negatively regulate polar auxi ... | 2007 | 17908155 |
| medicinal smoke reduces airborne bacteria. | this study represents a comprehensive analysis and scientific validation of our ancient knowledge about the effect of ethnopharmacological aspects of natural products' smoke for therapy and health care on airborne bacterial composition and dynamics, using the biolog microplate panels and microlog database. we have observed that 1h treatment of medicinal smoke emanated by burning wood and a mixture of odoriferous and medicinal herbs (havan sámagri=material used in oblation to fire all over india) ... | 2007 | 17913417 |
| absence of the endo-beta-1,4-glucanases cel1 and cel2 reduces susceptibility to botrytis cinerea in tomato. | cel1 and cel2 are members of the tomato (solanum lycopersicum mill) endo-beta-1,4-glucanase (egase) family that may play a role in fruit ripening and organ abscission. this work demonstrates that cel1 protein is present in other vegetative tissues and accumulates during leaf development. we recently reported the downregulation of both the cel1 mrna and protein upon fungal infection, suggesting the involvement of egases in plant-pathogen interactions. this hypothesis was confirmed by assessing th ... | 2007 | 17916112 |
| a key role for the arabidopsis win3 protein in disease resistance triggered by pseudomonas syringae that secrete avrrpt2. | effector proteins injected by the pathogenic bacteria pseudomonas syringae into plants can have profound effects on the pathogen-host interaction due to their efficient recognition by plants and the subsequent triggering of defenses. the avrrpt2 effector triggers strong local and systemic defense (called systemic acquired resistance [sar]) responses in arabidopsis thaliana plants that harbor a functional rps2 gene that encodes an r protein in the coiled-coil, nucleotide-binding domain, leucine-r ... | 2007 | 17918621 |
| distribution and replication of the pathogenicity plasmid ppath in diverse populations of the gall-forming bacterium pantoea agglomerans. | pantoea agglomerans has been transformed from a commensal bacterium into two related gall-forming pathovars by acquisition of ppath plasmids containing a pathogenicity island (pai). this pai harbors an hrp/hrc gene cluster, type iii effectors, and phytohormone biosynthetic genes. dna typing by pulsed-field gel electrophoresis revealed two major groups of p. agglomerans pv. gypsophilae and one group of p. agglomerans pv. betae. the ppath plasmids of the different groups had nearly identical repli ... | 2007 | 17921271 |
| erwinia carotovora elicitors and botrytis cinerea activate defense responses in physcomitrella patens. | vascular plants respond to pathogens by activating a diverse array of defense mechanisms. studies with these plants have provided a wealth of information on pathogen recognition, signal transduction and the activation of defense responses. however, very little is known about the infection and defense responses of the bryophyte, physcomitrella patens, to well-studied phytopathogens. the purpose of this study was to determine: i) whether two representative broad host range pathogens, erwinia carot ... | 2007 | 17922917 |
| a novel relaxase homologue is involved in chromosomal dna processing for type iv secretion in neisseria gonorrhoeae. | the neisseria gonorrhoeae type iv secretion system secretes chromosomal dna that acts in natural transformation. to examine the mechanism of dna processing for secretion, we made mutations in the putative relaxase gene trai and used nucleases to characterize the secreted dna. the nuclease experiments demonstrated that the secreted dna is single-stranded and blocked at the 5' end. mutation of trai identified tyr93 as required for dna secretion, while substitution of tyr201 resulted in intermediat ... | 2007 | 17927698 |
| comparative and functional genomics reveals genetic diversity and determinants of host specificity among reference strains and a large collection of chinese isolates of the phytopathogen xanthomonas campestris pv. campestris. | xanthomonas campestris pathovar campestris (xcc) is the causal agent of black rot disease of crucifers worldwide. the molecular genetic diversity and host specificity of xcc are poorly understood. | 2007 | 17927820 |
| layered basal defenses underlie non-host resistance of arabidopsis to pseudomonas syringae pv. phaseolicola. | arabidopsis is a non-host for pseudomonas syringae pv. phaseolicola nps3121 (pph), a bacterial pathogen of bean. pph does not induce a hypersensitive response in arabidopsis. here we show that arabidopsis instead resists pph with multi-layered basal defense. our approach was: (i) to identify defense readouts induced by pph; (ii) to determine whether mutations in known arabidopsis defense genes disrupt pph-induced defense signaling; (iii) to determine whether heterologous type iii effectors from ... | 2007 | 17573803 |
| essential role of cytochrome bd-related oxidase in cyanide resistance of pseudomonas pseudoalcaligenes cect5344. | pseudomonas pseudoalcaligenes cect5344 grows in minimal medium containing cyanide as the sole nitrogen source. under these conditions, an o2-dependent respiration highly resistant to cyanide was detected in cell extracts. the structural genes for the cyanide-resistant terminal oxidase, cioa and ciob, are clustered and encode the integral membrane proteins that correspond to subunits i and ii of classical cytochrome bd, although the presence of heme d in the membrane could not be detected by diff ... | 2007 | 17574992 |
| regulation of plant innate immunity by three proteins in a complex conserved across the plant and animal kingdoms. | innate immunity against pathogen infection is an evolutionarily conserved process among multicellular organisms. arabidopsis snc1 encodes a resistance protein that combines attributes of multiple mammalian pattern recognition receptors. utilizing snc1 as an autoimmune model, we identified a discrete protein complex containing at least three members--mos4 (modifier of snc1, 4), atcdc5, and prl1 (pleiotropic regulatory locus 1)--that are all essential for plant innate immunity. atcdc5 has dna-bind ... | 2007 | 17575050 |
| expression of a metacaspase gene of nicotiana benthamiana after inoculation with colletotrichum destructivum or pseudomonas syringae pv. tomato, and the effect of silencing the gene on the host response. | metacaspases are cysteine proteinases that have homology to caspases, which play a central role in signaling and executing programmed cell death in animals. a type ii metacaspase cdna, nbmca1, was amplified from nicotiana benthamiana infected with colletotrichum destructivum. it showed a peak in expression at 72 h post-inoculation corresponding with the switch to necrotrophy by c. destructivum. inoculation of n. benthamiana with an incompatible bacterium, pseudomonas syringae pv. tomato, which s ... | 2007 | 17576564 |
| case study of combinatorial imaging: what protocol and what chlorophyll fluorescence image to use when visualizing infection of arabidopsis thaliana by pseudomonas syringae? | localized infection of a plant can be mapped by a sequence of images capturing chlorophyll fluorescence transients in actinic light. choice of the actinic light protocol co-determines fluorescence contrast between infected leaf segment and surrounding healthy tissue. frequently, biology cannot predict with which irradiance protocol, in which fluorescence image of the sequence, and in which segment of the image there will be the highest contrast between the healthy and infected tissue. here, we i ... | 2007 | 17211582 |
| phylogenetic tree information aids supervised learning for predicting protein-protein interaction based on distance matrices. | protein-protein interactions are critical for cellular functions. recently developed computational approaches for predicting protein-protein interactions utilize co-evolutionary information of the interacting partners, e.g., correlations between distance matrices, where each matrix stores the pairwise distances between a protein and its orthologs from a group of reference genomes. | 2007 | 17212819 |
| functional analysis of arabidopsis wrky25 transcription factor in plant defense against pseudomonas syringae. | a common feature of plant defense responses is the transcriptional regulation of a large number of genes upon pathogen infection or treatment with pathogen elicitors. a large body of evidence suggests that plant wrky transcription factors are involved in plant defense including transcriptional regulation of plant host genes in response to pathogen infection. however, there is only limited information about the roles of specific wrky dna-binding transcription factors in plant defense. | 2007 | 17214894 |
| arabidopsis systemic immunity uses conserved defense signaling pathways and is mediated by jasmonates. | in the absence of adaptive immunity displayed by animals, plants respond locally to biotic challenge via inducible basal defense networks activated through recognition and response to conserved pathogen-associated molecular patterns. in addition, immunity can be induced in tissues remote from infection sites by systemic acquired resistance (sar), initiated after gene-for-gene recognition between plant resistance proteins and microbial effectors. the nature of the mobile signal and remotely activ ... | 2007 | 17215350 |
| the n-terminal region of pseudomonas type iii effector avrptob elicits pto-dependent immunity and has two distinct virulence determinants. | resistance to bacterial speck disease in tomato is activated by the physical interaction of the host pto kinase with either of the sequence-dissimilar type iii effector proteins avrpto or avrptob (hopab2) from pseudomonas syringae pv. tomato. pto-mediated immunity requires prf, a protein with a nucleotide-binding site and leucine-rich repeats. the n-terminal 307 amino acids of avrptob were previously reported to interact with the pto kinase, and we show here that this region (avrptob(1-307)) is ... | 2007 | 17764515 |
| virulence and prodigiosin antibiotic biosynthesis in serratia are regulated pleiotropically by the ggdef/eal domain protein, pigx. | gram-negative bacteria of the genus serratia are opportunistic human, plant, and insect pathogens. serratia sp. strain atcc 39006 secretes pectinases and cellulases and produces the secondary metabolites carbapenem and prodigiosin. mutation of a gene (pigx) resulted in an extremely pleiotropic phenotype: prodigiosin antibiotic biosynthesis, plant virulence, and pectinase production were all elevated. pigx controlled secondary metabolism by repressing the transcription of the target prodigiosin b ... | 2007 | 17766413 |
| pseudomonas syringae lytic transglycosylases coregulated with the type iii secretion system contribute to the translocation of effector proteins into plant cells. | pseudomonas syringae translocates virulence effector proteins into plant cells via a type iii secretion system (t3ss) encoded by hrp (for hypersensitive response and pathogenicity) genes. three genes coregulated with the hrp t3ss system in p. syringae pv. tomato dc3000 have predicted lytic transglycosylase domains: pspto1378 (here designated hrph), pspto2678 (hopp1), and pspto852 (hopaj1). hrph is located between hrpr and avre1 in the hrp pathogenicity island and is carried in the functional clu ... | 2007 | 17827286 |
| physiological ecology of stenoxybacter acetivorans, an obligate microaerophile in termite guts. | stenoxybacter acetivorans is a newly described, obligately microaerophilic beta-proteobacterium that is abundant in the acetate-rich hindgut of reticulitermes. here we tested the hypotheses that cells are located in the hypoxic, peripheral region of reticulitermes flavipes hindguts and use acetate to fuel their o(2)-consuming respiratory activity in situ. physical fractionation of r. flavipes guts, followed by limited-cycle pcr with s. acetivorans-specific 16s rrna gene primers, indicated that c ... | 2007 | 17827335 |
| exoribonuclease r in mycoplasma genitalium can carry out both rna processing and degradative functions and is sensitive to rna ribose methylation. | mycoplasma genitalium, a small bacterium having minimal genome size, has only one identified exoribonuclease, rnase r (mgr). we have purified mgr to homogeneity, and compared its rna degradative properties to those of its escherichia coli homologs rnase r (ecr) and rnase ii (ecii). mgr is active on a number of substrates including oligoribonucleotides, poly(a), rrna, and precursors to trna. unlike ecr, which degrades rrna and pre-trna without formation of intermediate products, mgr appears sensi ... | 2007 | 17872508 |
| identification of harpins in pseudomonas syringae pv. tomato dc3000, which are functionally similar to hrpk1 in promoting translocation of type iii secretion system effectors. | harpins are a subset of type iii secretion system (t3ss) substrates found in all phytopathogenic bacteria that utilize a t3ss. pseudomonas syringae pv. tomato dc3000 was previously reported to produce two harpins, hrpz1 and hrpw1. dc3000 was shown here to deploy two additional proteins, hopak1 and hopp1, which have the harpin-like properties of lacking cysteine, eliciting the hypersensitive response (hr) when partially purified and infiltrated into tobacco leaves, and possessing a two-domain str ... | 2007 | 17873033 |
| the pseudomonas syringae type iii effector tyrosine phosphatase hopao1 suppresses innate immunity in arabidopsis thaliana. | the bacterial pathogen pseudomonas syringae pv. tomato (pst) strain dc3000 infects tomato and arabidopsis plants, and is a model for studying the molecular basis of bacterial disease. pst dc3000 secretes a battery of largely uncharacterized effector proteins into host cells via a type-iii secretion system (ttss). little is currently known about the molecular mechanisms by which individual ttss effectors promote virulence. the effector hopao1 has similarity to protein tyrosine phosphatases, inclu ... | 2007 | 17877704 |
| evaluation of reference genes for real-time rt-pcr expression studies in the plant pathogen pectobacterium atrosepticum. | real-time rt-pcr has become a powerful technique to monitor low-abundance mrna expression and is a useful tool when examining bacterial gene expression inside infected host tissues. however, correct evaluation of data requires accurate and reliable normalisation against internal standards. thus, the identification of reference genes whose expression does not change during the course of the experiment is of paramount importance. here, we present a study where manipulation of cultural growth condi ... | 2007 | 17888160 |
| the ralstonia solanacearum pathogenicity regulator hrpb induces 3-hydroxy-oxindole synthesis. | the transcriptional activator hrpb of the bacterial wilt causing betaproteobacterium ralstonia solanacearum represents a key regulator for pathogenicity. in particular, it drives expression of hrp genes encoding a type iii secretion system (t3ss) as well as effector molecules for delivery into the host cytosol to promote disease. however, the hrpb regulon extends beyond this t3ss. we describe here an hrpb-activated operon of six genes that is responsible for the synthesis of a fluorescent isatin ... | 2007 | 17890323 |
| a cluster of disease resistance genes in arabidopsis is coordinately regulated by transcriptional activation and rna silencing. | the rpp5 (for recognition of peronospora parasitica 5) locus in the arabidopsis thaliana columbia strain contains a cluster of paralogous disease resistance (r) genes that play important roles in innate immunity. among the r genes in this locus, rpp4 confers resistance to two races of the fungal pathogen hyaloperonospora parasitica, while activation of snc1 (for suppressor of npr1-1, constitutive 1) results in the resistance to another race of h. parasitica and to pathovars of the bacterial path ... | 2007 | 17890374 |
| rice pti1a negatively regulates rar1-dependent defense responses. | tomato (solanum lycopersicum) pto encodes a protein kinase that confers resistance to bacterial speck disease. a second protein kinase, pti1, physically interacts with pto and is involved in pto-mediated defense signaling. pti1-related sequences are highly conserved among diverse plant species, including rice (oryza sativa), but their functions are largely unknown. here, we report the identification of a null mutant for the pti1 homolog in rice and the functional characterization of os pti1a. th ... | 2007 | 17890377 |
| deinococcus geothermalis: the pool of extreme radiation resistance genes shrinks. | bacteria of the genus deinococcus are extremely resistant to ionizing radiation (ir), ultraviolet light (uv) and desiccation. the mesophile deinococcus radiodurans was the first member of this group whose genome was completely sequenced. analysis of the genome sequence of d. radiodurans, however, failed to identify unique dna repair systems. to further delineate the genes underlying the resistance phenotypes, we report the whole-genome sequence of a second deinococcus species, the thermophile de ... | 2007 | 17895995 |
| wounding induces resistance to pathogens with different lifestyles in tomato: role of ethylene in cross-protection. | many reports point to the existence of a network of regulatory signalling occurring in plants during the interaction with micro-organisms (biotic stress) and abiotic stresses such as wounding. however, the focus is on shared intermediates/components and/or common molecular outputs in differently triggered signalling pathways, and not on the degree and modes of effective influence between abiotic and biotic stresses nor the range of true plant-pathogen interactions open to such influence. we repo ... | 2007 | 17897407 |
| the pseudomonas putida lon protease is involved in n-acyl homoserine lactone quorum sensing regulation. | in pseudomonas putida and pseduomonas aeruginosa, the similar ppur/rsal/ppui and lasr/rsal/lasi acyl homoserine lactones (ahls) quorum sensing (qs) systems have been shown to be under considerable regulation by other global regulators. a major regulator is the rsal protein which strongly directly represses the transcription of the p. putida ppui and p. aeruginosa lasi ahl synthases. in this study we screened a transposon mutant bank of p. putida in order to identify if any other regulators were ... | 2007 | 17655747 |
| the plant host pathogen interface: cell wall and membrane dynamics of pathogen-induced responses. | perception of pathogens by their hosts is the outcome of a highly coordinated and sophisticated surveillance network, tightly regulated by both host and pathogen elicitors, effectors, and signaling processes. in this article, we focus on two relatively well-studied host-pathogens systems, one involving a bacterial-plant interaction (pseudomonas syringae-arabidopsis) and the other involving an oomycete-plant interaction (phytophthora sojae-soybean). we discuss the status of current research relat ... | 2007 | 17656566 |
| characterization of the osmoprotectant transporter opuc from pseudomonas syringae and demonstration that cystathionine-beta-synthase domains are required for its osmoregulatory function. | the plant pathogen pseudomonas syringae may cope with osmotic stress on plants, in part, by importing osmoprotective compounds. in this study, we found that p. syringae pv. tomato strain dc3000 was distinct from most bacterial species in deriving greater osmoprotection from exogenous choline than from glycine betaine. this superior osmoprotection was correlated with a higher capacity for uptake of choline than for uptake of glycine betaine. of four putative osmoregulatory abc transporters in dc3 ... | 2007 | 17660277 |
| salicylic acid, yersiniabactin, and pyoverdin production by the model phytopathogen pseudomonas syringae pv. tomato dc3000: synthesis, regulation, and impact on tomato and arabidopsis host plants. | a genetically tractable model plant pathosystem, pseudomonas syringae pv. tomato dc3000 on tomato and arabidopsis thaliana hosts, was used to investigate the role of salicylic acid (sa) and iron acquisition via siderophores in bacterial virulence. pathogen-induced sa accumulation mediates defense in these plants, and dc3000 contains the genes required for the synthesis of sa, the sa-incorporated siderophore yersiniabactin (ybt), and the fluorescent siderophore pyoverdin (pvd). we found that dc30 ... | 2007 | 17660289 |
| atnudt7, a negative regulator of basal immunity in arabidopsis, modulates two distinct defense response pathways and is involved in maintaining redox homeostasis. | plants have evolved complicated regulatory systems to control immune responses. both positive and negative signaling pathways interplay to coordinate development of a resistance response with the appropriate amplitude and duration. atnudt7, a nudix domain-containing protein in arabidopsis (arabidopsis thaliana) that hydrolyzes nucleotide derivatives, was found to be a negative regulator of the basal defense response, and its loss-of-function mutation results in enhanced resistance to infection b ... | 2007 | 17660350 |
| a novel insertion sequence, ispa26, in oprd of pseudomonas aeruginosa is associated with carbapenem resistance. | 2007 | 17682099 | |
| identification of discriminative characteristics for clusters from biologic data with inforbio software. | there are a number of different methods for generation of trees and algorithms for phylogenetic analysis in the study of bacterial taxonomy. genotypic information, such as ssu rrna gene sequences, now plays a more prominent role in microbial systematics than does phenotypic information. however, the integration of genotypic and phenotypic information for polyphasic studies is necessary for the classification and identification of microbes. thus, we devised an algorithm that objectively identifie ... | 2007 | 17683520 |
| an "electronic fluorescent pictograph" browser for exploring and analyzing large-scale biological data sets. | the exploration of microarray data and data from other high-throughput projects for hypothesis generation has become a vital aspect of post-genomic research. for the non-bioinformatics specialist, however, many of the currently available tools provide overwhelming amounts of data that are presented in a non-intuitive way. | 2007 | 17684564 |
| the structural basis for activation of plant immunity by bacterial effector protein avrpto. | pathogenic microbes use effectors to enhance susceptibility in host plants. however, plants have evolved a sophisticated immune system to detect these effectors using cognate disease resistance proteins, a recognition that is highly specific, often elicits rapid and localized cell death, known as a hypersensitive response, and thus potentially limits pathogen growth. despite numerous genetic and biochemical studies on the interactions between pathogen effector proteins and plant resistance prote ... | 2007 | 17694048 |
| dual regulation role of gh3.5 in salicylic acid and auxin signaling during arabidopsis-pseudomonas syringae interaction. | salicylic acid (sa) plays a central role in plant disease resistance, and emerging evidence indicates that auxin, an essential plant hormone in regulating plant growth and development, is involved in plant disease susceptibility. gh3.5, a member of the gh3 family of early auxin-responsive genes in arabidopsis (arabidopsis thaliana), encodes a protein possessing in vitro adenylation activity on both indole-3-acetic acid (iaa) and sa. here, we show that gh3.5 acts as a bifunctional modulator in bo ... | 2007 | 17704230 |
| athipm, an ortholog of the apple hrpn-interacting protein, is a negative regulator of plant growth and mediates the growth-enhancing effect of hrpn in arabidopsis. | hrpn (harpin) protein is critical to the virulence of the fire blight pathogen erwinia amylovora in host plants like apple (malus x domestica). moreover, exogenous treatment of arabidopsis (arabidopsis thaliana), a nonhost plant, with partially purified hrpn enhances growth. to address the bases of the effects of hrpn in disease, we sought a hrpn-interacting protein(s) in apple, using a yeast two-hybrid assay. a single positive clone, designated hipm (hrpn-interacting protein from malus), was fo ... | 2007 | 17704235 |
| pseudomonas syringae type iii effector avrptob is phosphorylated in plant cells on serine 258, promoting its virulence activity. | the pseudomonas syringae pv. tomato protein avrptob is translocated into plant cells via the bacterial type iii secretion system. in resistant tomato leaves, avrptob acts as an avirulence protein by interacting with the host pto kinase and eliciting the host immune response. pto-mediated immunity requires prf, a pto-interacting protein with a putative nucleotide-binding site and a region of leucine-rich repeats. in susceptible tomato plants, which lack either pto or prf, avrptob acts as a virule ... | 2007 | 17711844 |
| characterization of arabidopsis thaliana genes encoding functional homologues of the yeast metal chaperone cox19p, involved in cytochrome c oxidase biogenesis. | the arabidopsis thaliana genome contains two nearly identical genes which encode proteins showing similarity with the yeast metal chaperone cox19p, involved in cytochrome c oxidase biogenesis. one of these genes (atcox19-1) produces two transcript forms that arise from an alternative splicing event and encode proteins with different n-terminal portions. both atcox19 isoforms are imported into mitochondria in vitro and are found attached to the inner membrane facing the intermembrane space. the s ... | 2007 | 17712601 |
| blue-light-activated histidine kinases: two-component sensors in bacteria. | histidine kinases, used for environmental sensing by bacterial two-component systems, are involved in regulation of bacterial gene expression, chemotaxis, phototaxis, and virulence. flavin-containing domains function as light-sensory modules in plant and algal phototropins and in fungal blue-light receptors. we have discovered that the prokaryotes brucella melitensis, brucella abortus, erythrobacter litoralis, and pseudomonas syringae contain light-activated histidine kinases that bind a flavin ... | 2007 | 17717187 |
| role of phages in the pathogenesis of burkholderia, or 'where are the toxin genes in burkholderia phages?'. | most bacteria of the genus burkholderia are soil- and rhizosphere-associated, and rhizosphere associated, noted for their metabolic plasticity in the utilization of a wide range of organic compounds as carbon sources. many burkholderia species are also opportunistic human and plant pathogens, and the distinction between environmental, plant, and human pathogens is not always clear. burkholderia phages are not uncommon and multiple cryptic prophages are identifiable in the sequenced burkholderia ... | 2007 | 17719265 |
| ethylene is one of the key elements for cell death and defense response control in the arabidopsis lesion mimic mutant vad1. | although ethylene is involved in the complex cross talk of signaling pathways regulating plant defense responses to microbial attack, its functions remain to be elucidated. the lesion mimic mutant vad1-1 (for vascular associated death), which exhibits the light-conditional appearance of propagative hypersensitive response-like lesions along the vascular system, is a good model for studying the role of ethylene in programmed cell death and defense. here, we demonstrate that expression of genes as ... | 2007 | 17720753 |