Project description:Pseudomonas syringae pv. syringae 9644 (Pss9644) is a causal agent of bacterial cherry canker causing necrotic symptoms on leaves, fruits, gummosis and canker in woody tissues of sweet cherry (Prunus avium). To understand which virulent factor genes were expressed in vitro, Pss9644 was grown in rich media (King's B Broth) and minimum media (hrp-inducing minimum media). The latter mimics the in planta environment.
Project description:To study the responses of kiwifruit to Pseudomonas syringae pv. actinidiae, one-year-old potted seeding A. c. var. deliciosa cultivar ‘Jinkui’ and the pandemic Pseudomonas syringae pv. actinidiae bacterial strain JF8 (CCTCC AB2018305) were used for this study. This bacterial strain was originally isolated from A. c. var. chinensis cultivar ‘Jinfeng’ and further characterized . Plants were maintained in an aseptic room, with 95% of relative humidity, have natural light and no further fertilization after their receiving from the nursery. For inoculation, the P. s.pv. actinidiae strain was streaked on nutrient-sucrose agar (NSA) and incubated at 25 °C for 48-h. Ten microliters of a bacterial suspension (1-2×107cfu/mL) prepared in sterile 0.85 % w NaCl were inoculated in the plants chosen for investigation. The bacterial suspension was sprayed to entirety tree. In parallel, control plants were treated in the same way with sterile 0.85 % w NaCl solution. The inoculated and control plants were randomly distributed in the room at 15 ± 3 °C. 24-h after inoculation, ‘Jinkui’ leaves were sampled from the infected and control plants for further analyses. Each sample consisted of the leaves of one tree. Three biological replicates were used for each line.
Project description:Pseudomonas syringae pv. actinidiae biovar 6 (Psa6) is a causal agent of kiwifruit bacterial canker and is a unique plant pathogenic bacterium, producing two types of phytotoxins, coronatine and phaseolotoxin. We investigated the expression behavior of virulent genes of Psa6 under various culture conditions.
Project description:Purpose: Pseudomonas syringae pv. actinidiae (Psa) is a phytopathogen that causes devastating bacterial canker in kiwifruit. Among five biovars defined by genetic, biochemical and virulence traits, Psa3 is the most aggressive and is responsible for the most recent reported outbreaks, but the molecular basis of its heightened virulence is unclear. A custom P. syringae multi-strain whole-genome microarray platform, encompassing biovars Psa1, Psa2 and Psa3 and the well-established model P. syringae pv. tomato, was used to analyse early bacterial responses to an apoplast-like minimal medium. Conlusion: this work highlighted that diverse early responses to the host apoplast, even among bacteria belonging to the same pathovar, can lead to different virulence strategies and may explain the differing outcomes of infections.
Project description:Transcription profiling of Nicotinan benthamiana in response to Pectobacterium carotovorum WPP14 and Pseudomonas syringae pv. tomato DC3000
Project description:Compare expression profiles between Col-0 and transgenic lines overexpressing AtFAAH(At5g64440) after inoculated with nonhost pathogen Pseudomonas syringae pv. syringae at 0, 6 and 12 hours.
Project description:Expression profiling of wild-type plants and mutants with defects in key components of the defense signaling network was used to model the Arabidopsis network 24 hours after infection by Pseudomonas syringae pv. maculicola strain Psm ES4326. Results using the Affymetrix ATH1 array revealed that expression levels of most pathogen-responsive genes were affected by mutations in coi1, ein2, npr1, pad4, or sid2. These five mutations defined a small number of different expression patterns displayed by the majority of pathogen-responsive genes. P. syringae pv. tomato strain Pst DC3000 elicited a much weaker salicylic acid response than Psm ES4326. Additional mutants were profiled using a custom array. Profiles of pbs3 and ndr1 revealed major effects of these mutations and allowed PBS3 and NDR1 to be placed between the EDS1/PAD4 node and the SA synthesis node in the defense network. Comparison of coi1, dde2, and jar1 profiles showed that many genes were affected by coi1, but very few were affected by dde2 or jar1. Profiles of coi1 plants infected with Psm ES4326 were very similar to those of wild-type plants infected with bacteria unable to produce the phytotoxin coronatine, indicating that essentially all COI1-dependent gene expression changes in this system are caused by coronatine.
Project description:Purpose: The outcome of host–pathogen interactions is thought to reflect the offensive and defensive capabilities of both players. When plants interact with Pseudomonas syringae, several well-characterized virulence factors contribute to early bacterial pathogenicity, including the type III secretion system (T3SS), which must be activated by signals from the plant and environment to allow the secretion of virulence effectors. The manner in which these signals regulate T3SS activity is still unclear. Conlusion: the analysis revealed that the perception of plant signals from kiwifruit or tomato extracts anticipates T3SS expression in P. syringae pv. actinidiae compared to apoplast-like conditions