| differentiation between xanthomonas campestris pv. oryzae, xanthomonas campestris pv. oryzicola and the bacterial 'brown blotch' pathogen on rice by numerical analysis of phenotypic features and protein gel electrophoregrams. | thirty-five xanthomonas campestris pv. oryzae, fourteen x. campestris pv. oryzicola strains and six 'brown blotch' pathogens of rice, all of different geographical origin, were studied by numerical analysis of 133 phenotype features and gel electrophoregrams of soluble proteins, %g + c determinations and dna:rrna hybridizations. the following conclusions were drawn. (i) the xanthomonas campestris pathovars oryzae and oryzicola display clearly distinct protein patterns on polyacrylamide gels and ... | 1984 | 6084704 |
| exopolysaccharides of xanthomonas pathovar strains that infect rice and wheat crops. | in order to understand the mode of action of the taxonomically related pathogens xanthomonas campestris pv. translucens, xanthomonas oryzae pv. oryzae, and xanthomonas oryzae pv. oryzicola, which attack wheat and rice crops, we examined the compositional differences of their exopolysaccharides (epss). maximum production of polysaccharide in shake cultures of these pathogens was observed between 24 and 72 h. x. campestris pv. translucens, the leaf streak pathogen of wheat, produced a higher amoun ... | 2001 | 11525629 |
| the rxo1/ rba1 locus of maize controls resistance reactions to pathogenic and non-host bacteria. | infiltration of different maize lines with a variety of bacterial pathogens of maize, rice and sorghum identified qualitative differences in resistant reactions. isolates from two bacterial species induced rapid hypersensitive reactions (hr) in some maize lines, but not others. all isolates of the non-host pathogen xanthomonas oryzae pv. oryzicola (bacterial leaf streak disease of rice) and some isolates of the pathogenic bacterium burkholderia andropogonis induced hr when infiltrated into maize ... | 2004 | 15114472 |
| the avrrxo1 gene from the rice pathogen xanthomonas oryzae pv. oryzicola confers a nonhost defense reaction on maize with resistance gene rxo1. | maize lines that contain the single dominant gene rxo1 exhibit a rapid hypersensitive response (hr) after infiltration with the rice bacterial streak pathogen xanthomonas oryzae pv. oryzicola, but not with the rice bacterial blight pathogen x. oryzae pv. oryzae. the avirulence effector gene that corresponds to rxo1, designated avrrxo1, was identified in an x. oryzae pv. oryzicola genomic library. when introduced into x. oryzae pv. oryzae, clones containing avrrxo1 induced an hr on maize with rxo ... | 2004 | 15242171 |
| variation suggestive of horizontal gene transfer at a lipopolysaccharide (lps) biosynthetic locus in xanthomonas oryzae pv. oryzae, the bacterial leaf blight pathogen of rice. | in animal pathogenic bacteria, horizontal gene transfer events (hgt) have been frequently observed in genomic regions that encode functions involved in biosynthesis of the outer membrane located lipopolysaccharide (lps). as a result, different strains of the same pathogen can have substantially different lps biosynthetic gene clusters. since lps is highly antigenic, the variation at lps loci is attributed to be of advantage in evading the host immune system. although lps has been suggested as a ... | 2004 | 15473911 |
| a maize resistance gene functions against bacterial streak disease in rice. | although cereal crops all belong to the grass family (poacea), most of their diseases are specific to a particular species. thus, a given cereal species is typically resistant to diseases of other grasses, and this nonhost resistance is generally stable. to determine the feasibility of transferring nonhost resistance genes (r genes) between distantly related grasses to control specific diseases, we identified a maize r gene that recognizes a rice pathogen, xanthomonas oryzae pv. oryzicola, which ... | 2005 | 16230639 |
| [detection and identification of xanthomonas oryzae pv. oryzae and xanthomonas oryzae pv. oryzicola by real-time fluorescent pcr]. | a novel and sensitive real time pcr was developed to detection xanthomonas oryzae pv. oryzae and xanthomonas oryzae pv. oryzicola, which cause the bacteria leaf blight (blb) and leaf streak respectively, universal and specific taqman probes, which were designed based on the sequence of putative siderophore receptor gene cds were used to detect 13 bacteria and one phytoplasmas, only in x. oryzae pv. oryzae and x. oryzae pv. oryzicola, fluorescent signal can be collected with their specific probes ... | 2003 | 16281561 |
| inhibition of resistance gene-mediated defense in rice by xanthomonas oryzae pv. oryzicola. | xanthomonas oryzae pv. oryzae and the closely related x. oryzae pv. oryzicola cause bacterial blight and bacterial leaf streak of rice, respectively. although many rice resistance (r) genes and some corresponding avirulence (avr) genes have been characterized for bacterial blight, no endogenous avr/r gene interactions have been identified for leaf streak. genes avrxa7 and avrxa10 from x. oryzae pv. oryzae failed to elicit the plant defense-associated hypersensitive reaction (hr) and failed to pr ... | 2006 | 16570654 |
| elucidation of the hrp clusters of xanthomonas oryzae pv. oryzicola that control the hypersensitive response in nonhost tobacco and pathogenicity in susceptible host rice. | xanthomonas oryzae pv. oryzicola, the cause of bacterial leaf streak in rice, possesses clusters of hrp genes that determine its ability to elicit a hypersensitive response (hr) in nonhost tobacco and pathogenicity in host rice. a 27-kb region of the genome of x. oryzae pv. oryzicola (rs105) was identified and sequenced, revealing 10 hrp, 9 hrc (hrp conserved), and 8 hpa (hrp-associated) genes and 7 regulatory plant-inducible promoter boxes. while the region from hpa2 to hpab and the hrpf operon ... | 2006 | 16957248 |
| molecular and pathotypic characterization of new xanthomonas oryzae strains from west africa. | dna polymorphism analysis and pathogenicity assays were used to characterize strains of xanthomonas oryzae pv. oryzae and xanthomonas oryzae pv. oryzicola collected from rice leaves in west africa. restriction fragment length polymorphism (rflp), repetitive sequence-based polymerase chain reaction, fluorescent amplified fragment-length polymorphism (faflp) analyses were assessed for molecular characterization, while pathogenicity was tested by leaf clipping and leaf infiltration. dendrograms wer ... | 2007 | 17506331 |
| [cloning, sequencing and fuctional study of gaca gene from xanthomonas oryzae pv. oryzicola]. | a gaca homologue, designated gaca(xooc), was cloned from xanthomonas oryzae pv. oryzicola (xooc), a bacterium that causes leaf streak of rice, with degenerated primers by polymerase amplification reaction (pcr). ncbi blast search indicated that gaca(xooc) had a similar structure to that of other gaca proteins, and had a cheb (chemotaxis response regulator containing a chey-like receiver domain)domain. sequence comparison showed that the gaca(xooc) was conserved in the xanthomonas genus. homology ... | 2007 | 17552221 |
| [establishment of the hrp-inducing systems for the expression of the hrp genes of xanthomonas oryzae pv. oryzicola]. | the hrp genes of xanthomonas oryzae pv. oryzicola (xooc), which is the causal agent of bacterial leaf streak in rice, possesses the ability to elicit hypersensitive response on nonhost plants and the pathogenicity in host rice. in order to analyze the function of the hrp genes, we developed hrp-inducing systems using transcriptional hrp: :gfp fusions with the promoters of hrpx and hpa 1 of xooc. the levels of gfp protein expression indicated that the hrp gene expression in xooc was not efficient ... | 2007 | 17672294 |
| [introduction of a non-host gene rxo1 cloned from maize resistant to rice bacterial leaf streak into rice varieties]. | rice bacterial leaf streak,caused by xanthomonas oryzae pv. oryzicola is a destructive bacterial disease in china. single-gene resistance to x. oryzae pv. oryzicola has not been found in rice germplasm. a cloned non-host gene from maize with resistance to bacterial leaf streak, rxo1, was transferred into four chinese rice varieties through an agrobacterium-mediated system, including zhonghua11, 9804, c418 and minghui86. pcr and southern analysis of the transgenic plants revealed the integration ... | 2007 | 17822031 |
| productivity and biochemical properties of green tea in response to full-length and functional fragments of hpag xooc, a harpin protein from the bacterial rice leaf streak pathogen xanthomonas oryzae pv. oryzicola. | harpin proteins from plant pathogenic bacteria can stimulate hypersensitive cell death (hcd), drought tolerance, defence responses against pathogens and insects in plants, as well as enhance plant growth. recently, we identified nine functional fragments of hpag;xooc, a harpin protein from xanthomonas oryzae pv.oryzicola, the pathogen that causes bacterial leaf streak in rice. fragments hpag;1-94'hpag;10-42, and hpag;62-138, which contain the hpag;xooc regions of the amino acid sequence as indic ... | 2007 | 17954972 |
| 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 |
| specific detection of xanthomonas oryzae pv. oryzicola in infected rice plant by use of pcr assay targeting a membrane fusion protein gene. | successful control of xanthomonas oryzae pv. oryzicola, the causal agent of bacterial leaf streak, requires a specific and reliable diagnostic tool. a pathovar-specific pcr assay was developed for the rapid and accurate detection of the plant pathogenic bacterium xanthomonas oryzae pv. oryzicola in diseased plant. based on differences in a membrane fusion protein gene of xanthomonas oryzae pv. oryzicola and other microorganisms, which was generated from ncbi (http://www.ncbi.nlm.nih.gov/) and cm ... | 2008 | 18852502 |
| identification of specific fragments of hpag xooc, a harpin from xanthomonas oryzae pv. oryzicola, that induce disease resistance and enhance growth in plants. | harpin proteins from gram-negative plant-pathogenic bacteria can stimulate hypersensitive cell death (hcd) and pathogen defense as well as enhance growth in plants. two of these diverse activities clearly are beneficial and may depend on particular functional regions of the proteins. identification of beneficial and deleterious regions might facilitate the beneficial use of harpin-related proteins on crops without causing negative effects like cell death. here, we report the identification and t ... | 2008 | 18943254 |
| a fragment of the xanthomonas oryzae pv. oryzicola harpin hpag xooc reduces disease and increases yield of rice in extensive grower plantings. | harpins of phytopathogenic bacteria stimulate defense and plant growth in many types of plants, conferring disease resistance and enhanced yield. in a previous study, we characterized nine fragments of the harpin protein hpag(xooc) from xanthomonas oryzae pv. oryzicola for plant defense elicitation and plant growth stimulation activity relative to the intact protein. in plants grown under controlled conditions, the fragment hpag10-42 was more active in both regards than hpag(xooc). here, we demo ... | 2008 | 18943255 |
| the internal glycine-rich motif and cysteine suppress several effects of the hpag(xooc) protein in plants. | abstract hpag(xooc), produced by xanthomonas oryzae pv. oryzicola, is a member of harpin group of proteins that stimulate plant growth, hypersensitive cell death (hcd), and pathogen defense. the protein contains two copies of the glycine-rich motif (grm), a characteristic of harpins, and a cysteine, which is absent in other harpins. genetic modification generated the pro-tein mutants hpag(xooc)mg (mg) by deleting grms and hpag(xooc)c47t (c47t) by replacing cysteine with threonine. when applied t ... | 2006 | 18943492 |
| constitutive heterologous expression of avrxa27 in rice containing the r gene xa27 confers enhanced resistance to compatible xanthomonas oryzae strains. | the vascular pathogen xanthomonas oryzae pv. oryzae (xoo) and nonvascular pathogen xanthomonas oryzae pv. oryzicola (xoc) cause bacterial blight (bb) and bacterial leaf streak (bls) diseases of rice, respectively. we have previously identified the avirulence gene avrxa27 from xoo pxo99(a), which specifically induces the expression of the rice resistance gene xa27, ultimately leading to resistance against bb disease in rice. in this study, we have generated a transgenic rice line (l24) that expre ... | 2009 | 19161350 |
| expression of hpagxooc protein in bacillus subtilis and its biological functions. | hpagxooc, from rice pathogenic bacterium xanthomonas oryzae pv. oryzicola, is a member of the harpin group of proteins, eliciting hypersensitive cell death in non-host plants, inducing disease and insect resistance in plants, and enhancing plant growth. to express and secret the hpagxooc protein in bacillus subtilis, we constructed a recombinant expression vector pm43hf with stronger promoter p43 and signal peptide element nprb. the sds-page and western blot analysis demonstrated the expression ... | 2009 | 19307770 |
| a pair of allelic wrky genes play opposite roles in rice-bacteria interactions. | although allelic diversity of genes has been reported to play important roles in different physiological processes, information on allelic diversity of defense-responsive genes in host-pathogen interactions is limited. here, we report that a pair of allelic genes, oswrky45-1 and oswrky45-2, which encode proteins with a 10-amino acid difference, play opposite roles in rice (oryza sativa) resistance against bacterial pathogens. bacterial blight caused by xanthomonas oryzae pv oryzae (xoo), bacteri ... | 2009 | 19700558 |
| [expression of the hrcc, hrpe and hpa3 genes is not regulated by the hrpg and hrpx genes in a rice pathogen xanthomonas oryzae pv. oryzicola]. | the hrp (hypersensitive response on nonhost plants and pathogenicity in host plants) gene cluster, which conforms xanthomonas oryzae pv. oryzicola, the causal agent of bacterial leaf streak in rice, to the ability to elicit a hypersensitive response (hr) in nonhost tobacco and pathogenicity in host rice, is thought to be regulated by the hrpg and hrpx genes. however, it is unclear whether the hrpg and hrpx genes regulate all the hrp gene expression of the cluster coordinately or not. | 2009 | 19835162 |
| assessment of inheritance pattern and agronomic performance of transgenic rapeseed having harpin xooc-encoding hrf2 gene. | hrf2 gene is a member of the harpin-encoding gene family of rice-pathogenic bacterium xanthomonas oryzae pv. oryzicola. in our previous studies, we observed that harpin(xooc) could elicit hypersensitive cell death in non-host plants, induce disease and insect resistance in plants, and enhance plant growth. in this study, the rapeseed cultivar, yangyou 4, was genetically engineered via agrobacterium-mediated transformation to express the hrf2 gene. polymerase chain reaction (pcr) and southern blo ... | 2010 | 20107894 |
| genome-wide gene responses in a transgenic rice line carrying the maize resistance gene rxo1 to the rice bacterial streak pathogen, xanthomonas oryzae pv. oryzicola. | non-host resistance in rice to its bacterial pathogen, xanthomonas oryzae pv. oryzicola (xoc), mediated by a maize nbs-lrr type r gene, rxo1 shows a typical hypersensitive reaction (hr) phenotype, but the molecular mechanism(s) underlying this type of non-host resistance remain largely unknown. | 2010 | 20122142 |
| genomic comparison between xanthomonas oryzae pv. oryzae and xanthomonas oryzae pv. oryzicola, using suppression-subtractive hybridization. | xanthomonas oryzae pathovar oryzae (xoo) and x. oryzae pv. oryzicola (xoc) cause bacterial diseases in rice: leaf blight and leaf streak, respectively. although both the asian and the african strains of xoo induce similar symptoms, they are genetically different, with the african xoo strains being more closely related to the asian xoc. to identify the sequences responsible for differences between african and asian xoo strains and their relatedness to xoc strains, a suppression-subtractive hybrid ... | 2010 | 20487016 |
| xanthomonas oryzae pathovars: model pathogens of a model crop. | summary xanthomonas oryzae pv. oryzae and xanthomonas oryzae pv. oryzicola cause bacterial blight and bacterial leaf streak of rice (oryza sativa), which constrain production of this staple crop in much of asia and parts of africa. tremendous progress has been made in characterizing the diseases and breeding for resistance. x. oryzae pv. oryzae causes bacterial blight by invading the vascular tissue, while x. oryzae pv. oryzicola causes bacterial leaf streak by colonizing the parenchyma. in rice ... | 2006 | 20507449 |
| proteomic analysis of the regulatory function of dsf-dependent quorum sensing in xanthomonas oryzae pv. oryzicola. | xanthomonas oryzae pv. oryzicola (xoc), which caused bacterial leaf streak in rice, is a bacterial pathogen limited to the apoplast of the mesophyll tissue. the rpff that encodes diffusible signal factor (dsf) synthase, played a key role in the virulence of many plant pathogenic bacteria. in this study, the rpf gene cluster was cloned, and the rpff was deleted in xoc. it was observed that the rpff mutant lost the ability to produce dsf molecular, and exhibited a significant reduction of virulenc ... | 2010 | 20946946 |
| construction of a tn5-tagged mutant library of xanthomonas oryzae pv. oryzicola as an invaluable resource for functional genomics. | to genome-widely mine pathogenesis-related genes of xanthomonas oryzae pv. oryzicola (xoc), which is the casual agent of bacterial leaf streak resulting in significant yield loss and poor quality in rice, a tn5 transposon-mediated mutation library was generated. twenty-five thousand transformants were produced by using tn5 transposome, appropriately corresponding to 5 × orf coverage of the genome, and inoculated into rice and tobacco, individually and respectively, for screening candidate virule ... | 2010 | 21046389 |
| manipulating broad-spectrum disease resistance by suppressing pathogen-induced auxin accumulation in rice. | breeding crops with the quality of broad-spectrum disease resistance using genetic resources is one of the principal goals of crop improvement. however, the molecular mechanism of broad-spectrum resistance remains largely unknown. here, we show that gh3-2, encoding an indole-3-acetic acid (iaa)-amido synthetase, mediates a broad-spectrum resistance to bacterial xanthomonas oryzae pv oryzae and xanthomonas oryzae pv oryzicola and fungal magnaporthe grisea in rice (oryza sativa). iaa, the major fo ... | 2010 | 21071600 |
| hpa2 required by hrpf to translocate xanthomonas oryzae transcriptional activator-like effectors into rice for pathogenicity. | xanthomonas oryzae pv. oryzicola, the causative agent of bacterial leaf streak, injects a plethora of effectors through the type iii secretion system (t3ss) into rice cells to cause disease. the t3ss, encoded by the hrp genes, is essential for the pathogen to elicit the hypersensitive response (hr) in nonhost tobacco and for pathogenicity in host rice. whether or not a putative lytic transglycosylase, hpa2, interacts with a translocon protein, hrpf, to facilitate bacterial pathogenicity remains ... | 2011 | 21478322 |
| a novel regulatory role of hrpd6 in regulating hrp-hrc-hpa genes in xanthomonas oryzae pv. oryzicola. | xanthomonas oryzae pv. oryzicola, the causal agent of bacterial leaf streak in the model plant rice, possesses an hrp-hrc-hpa cluster that encodes a type iii secretion system (t3ss) through which t3ss effectors are injected into host cells to cause disease or trigger plant defenses. mutations in this cluster usually abolish the bacterial ability to cause hypersensitive response (hr) in nonhost tobacco and pathogenicity in host rice. in xanthomonas species these genes are generally assumed to be ... | 2011 | 21615204 |
| over-expression in the nucleotide-binding site-leucine rich repeat gene depg1 increases susceptibility to bacterial leaf streak disease in transgenic rice plants. | bacterial leaf streak of rice (bls) caused by xanthomonas oryzae pv. oryzicola (xoc) is a widely-spread disease in the main rice-producing areas of the world. investigating the genes that play roles in rice-xoc interactions helps us to understand the defense signaling pathway in rice. here we report a differentially expressed protein gene (depg1), which regulates susceptibility to bls. depg1 is a nucleotide-binding site (nbs)-leucine rich repeat (lrr) gene, and the deduced protein sequence of de ... | 2011 | 21717056 |
| a novel antimicrobial protein for plant protection consisting of a xanthomonas oryzae harpin and active domains of cecropin a and melittin. | discoveries about antimicrobial peptides and plant defence activators have made possible the de novo and rational design of novel peptides for use in crop protection. here we report a novel chimeric protein, hcm1, which was made by linking the active domains of cecropin a and melittin to the hypersensitive response (hr)-elicitor hpa1 of xanthomonas oryzae pv. oryzicola, the causal agent of rice bacterial leaf streak. the resulting chimeric protein maintained not only the hr-inducing property of ... | 2011 | 21895994 |
| multilocus sequence analysis and type iii effector repertoire mining provide new insights into the evolutionary history and virulence of xanthomonas oryzae. | multilocus sequence analysis (mlsa) and type iii effector (t3e) repertoire mining were performed to gain new insights into the genetic relatedness of xanthomonas oryzae pv. oryzae (xoo) and xanthomonas oryzae pv. oryzicola (xoc), two major bacterial pathogens of rice. based on a collection of 45 african and asian strains, we first sequenced and analysed three housekeeping genes by mlsa, bayesian clustering and a median-joining network approach. second, we investigated the distribution of 32 t3e ... | 2011 | 21929565 |
| identification of hrpx regulon genes in xanthomonas oryzae pv. oryzicola using a gfp visualization technique. | xanthomonas oryzae pv. oryzicola is the causal agent of bacterial leaf streak in rice and injects repertoires of t3s effectors (t3ses), which are normally regulated by a global regulator hrpx, into plant cells to suppress plant innate immunity for disease development. to establish a visualization technique to identify hrpx regulon genes in this pathogen, we chose six known or unknown t3se genes of x. oryzae pv. oryzicola (strain rs105) as the targets in this report. the promoters of these candid ... | 2011 | 21987378 |
| [analysis of the flgd and fige genes regulated by diffusible signal factor in xanthomonas oryzae pv. oryzicola]. | to investigate functions of flgdxoc and flgexoc genes regulated by diffusible signal factor (dsf) in xanthomonas oryzae pv. oryzicola(xoc)rs105. | 2011 | 22043789 |
| identification and characterisation of a novel gene hshb in xathomonas oryzae pv. oryzicola co-regulated by quorum sensing and clp. | virulence factors of xanthomonas oryzae pv. oryzicola (xoc), the causal agent of bacterial leaf streak in rice, are regulated by diffusible signal factor (dsf)-dependent quorum-sensing (qs) system (44). in this study, a novel pathogenicity-related gene, xoryp_010100018570 (named hshb), of xoc was characterized. hshb encodes a hydrolase with a putative signal peptide, which is a homolog of imidazolonepropionase (huti). bioinformatic analysis showed that hshb is relatively conserved in the genus x ... | 2011 | 22106829 |
| identification of seven genes of xanthomonas oryzae pv. oryzicola potentially involved in pathogenesis in rice. | xanthomonas oryzae pv. oryzicola (xoc) causes bacterial leaf streak (bls) in rice, an emerging and destructive disease worldwide. identification of key virulence factors is prerequisite for understanding the pathogenesis of xoc. in this study, a tn5-tagged mutant library of xoc strain rs105 was screened on rice, and 27 tn5 mutants were identified that were either nonpathogenic or showed reduced virulence in rice. fourteen of the nonpathogenic mutants were also unable to elicit the hypersensitiv ... | 2011 | 22075022 |
| [identification of extracellular polysaccharide-associated genes in xanthomonas oryzae pv. oryzicola]. | previously, seventeen extracellular polysaccharide-associated mutants of xanthomonas oryzae pv. oryzicola (xoc) were acquired from our randomly tn5-inserted mutant library. to know the tn5-inserted genes of these mutants and their contribution to eps production and virulence in rice, | 2011 | 22233054 |