Download or read book Identification and Secretion of Effectors from the Pseudomonas Syringae Type III Secretion System written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Hypersensitive Reaction in Plants to Pathogens written by Robert N. Goodman and published by American Phytopathological Society. This book was released on 1994 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nikolai Gogol’s short story is a sublime work of tragi-comedy. In it, he brilliantly ridicules the Ukrainian passion for litigation and reveals life as something really rather absurd. Ivan Ivanovich and Ivan Nikiforovich are the greatest of friends—until the day they begin a foolish quarrel that culminates in that very worst of insults: “And you, Ivan Ivanovich, are a goose.” From that moment on, not another word is spoken between them as they choose instead to fight out their differences in the courts. But it seems theirs is a lawsuit that is set to run for years and years.

Download or read book Pseudomonas Syringae Type III Secretion System and Effectors written by Zhengqing Fu and published by ProQuest. This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Identification and Characterization of Type III Secretion Effector Proteins in Gram negative Bacteria written by Ekaterina Mikhailovna Panina and published by . This book was released on 2007 with total page 432 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Identification and Characterization of Pseudomonas Syringae Type Three Effectors that Alter Auxin Responses written by Maria Soledad Nievas and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Pseudomonas syringae and related pathogens written by Nicola Sante Iacobellis and published by Springer Science & Business Media. This book was released on 2013-06-29 with total page 673 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume mainly reports on new and recent advancements on different aspects of Pseudomonas syringae, a plant pathogenic bacterial species that include a high number of pathogens of important crops, which is an interesting model organism in plant pathology. In addition some related fluorescent Pseudomonas spp., responsible of new and emerging diseases, as well as some pathogens previously included in the above genus and now classified in the genera Ralstonia, Acidovorax are also considered. The tremendous recent advancements on: the ecology and epidemiology and, in particular, the adaptation of P. syringae to stresses and adverse environmental conditions; the function and regulation of genes involved in the production of phytotoxins and on their mechanism of action in the interaction with the host cells; the structure, function and regulation of type three secretion system (TTSS) and the transport of the effectors proteins in the host cells; the possibility to control diseases through the induction of the systemic acquired resistance (SAR); the development of molecular techniques for the highly specific and sensible identification and detection of pathogens; the determination of the causal agents of new and emerging diseases as well the classification of the different pathovars of P. syringae; are reported in 76 chapters cured by leading scientist in the respective fields.

Download or read book Pseudomonas Syringae Pathogenesis written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Phytopathogenic Prokaryotes written by Mark S. Mount and published by . This book was released on 1982 with total page 568 pages. Available in PDF, EPUB and Kindle. Book excerpt: V.1 - Phytopathogenic prokaryotes; Concepts for plant interactions with prokaryotes; Prokaryote interactions on plant surfaces; Prokaryote interactions within the plant; v.2 - Epidemiology and dispersal; Host coevolution with the pathogen; Pathogen coevolution with the host; Strategies for control; Cultivation and preservation.

Download or read book Effectors in Plant Microbe Interactions written by Francis Martin and published by John Wiley & Sons. This book was released on 2012-01-03 with total page 442 pages. Available in PDF, EPUB and Kindle. Book excerpt: Plants and microbes interact in a complex relationship that can have both harmful and beneficial impacts on both plant and microbial communities. Effectors, secreted microbial molecules that alter plant processes and facilitate colonization, are central to understanding the complicated interplay between plants and microbes. Effectors in Plant-Microbe Interactions unlocks the molecular basis of this important class of microbial molecules and describes their diverse and complex interactions with host plants. Effectors in Plant Microbe Interactions is divided into five sections that take stock of the current knowledge on effectors of plant-associated organisms. Coverage ranges from the impact of bacterial, fungal and oomycete effectors on plant immunity and high-throughput genomic analysis of effectors to the function and trafficking of these microbial molecules. The final section looks at effectors secreted by other eukaryotic microbes that are the focus of current and future research efforts. Written by leading international experts in plant-microbe interactions, Effectors in Plant Microbe Interactions, will be an essential volume for plant biologists, microbiologists, pathologists, and geneticists.

Download or read book Identification of Novel Type III Secreted Effectors from Two Rhizobial Species written by Elizabeth Marie Lehto and published by . This book was released on 2010 with total page 172 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Patrum aegyptorum opera omnia written by and published by . This book was released on 1858 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Regulation of Type III Secretion System in Pseudomonas Syringae written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: P. syringae is a group of bacterial phytopathogens that can infect a wide variety of plants. These bacteria rely on the type III secretion system (TTSS) to deliver effectors into plant cells for infection. The TTSS genes, that encode the TTSS apparatus and the effectors, are repressed when bacteria grow in nutrient rich media but are strongly induced in the plants and in minimal medium (MM). Plant cutin monomers appear to negatively regulate the P. syringae TTSS genes. It is poorly understood how bacteria sense the environmental signals to regulate the TTSS genes. By genetic screen, four sets of transposon insertion mutants displaying aberrant TTSS gene expression were isolated: KB and fin mutants derepress the TTSS genes in rich medium KB and in the presence of a cutin monomer precursor in MM, respectively; min and pin mutants are defective in induction of TTSS genes in MM and in plants, respectively. A putative two-component sensor histidine kinase, RohS, is identified to be required for the induction of avrPto-LUC in MM and in plants. The rohS gene is in an operon containing a two-component response regulator gene rohR. Mutation of rohS in P. s. phaseolicola and P. s. tomato reduced the bacterial pathogenicity on hosts and HR-inducing activity on non-hosts. Our results suggested that RohS acts upstream of HrpR/HrpS. The phosphorylated RohR represses TTSS genes. It is likely that RohS acts as phosphatase of RohR in the TTSS-inducing conditions, and subsequently derepresses TTSS genes. Simple sugars such as glucose, sucrose and fructose are known to be inducers of the TTSS genes. Isolation of four min mutants defective in fructose-uptake enabled us to study if sugars serve as extracellular signals or as essential nutrients. Our results suggest that fructose acts as an essential nutrient for the activation of type III genes. These mutants slightly compromised induction of avrPto promoter in Arabidopsis and pathogenicity on the host bean plant, but displayed normal HR elicitation on non-host plant tobacco. The reduced pathogenicity suggested that exploitation of fructose from the host tissue is an important means for pathogenesis of P. s. phaseolicola.

Download or read book Characterization of Effectors from the Type III Protein Secretion System of Pseudomonas Syringae Pv Tomato DC3000 written by Misty D. Janes Wehling and published by . This book was released on 2004 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Environmental and Density dependent Modulation of Type III Secretion System Genes in Pseudomonas Syringae Pv Tomato DC30 written by and published by . This book was released on 2010 with total page 121 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pseudomonas syringae pathovar tomato strain DC3000 is a model bacterial plant-pathogen that utilizes a dedicated protein export apparatus, the type III secretion system (T3SS), to translocate virulence proteins called effectors directly into host cells. Because effectors suppress plant immune responses, activation of the T3SS is critical upon entry into the host. The P. syringae T3SS is controlled by the hrpRS-hrpL regulatory cascade, and is activated quickly by specific conditions. Different environmental stimuli have been reported to modulate T3SS gene expression in culture, however it is unclear how each signal affects hrpRS or hrpL. My objective was to identify how environmental variables activate or repress hrpRS or hrpL in Pst DC3000. To this aim, I created three T3SS::gusA transcriptional reporter strains by fusing a promoterless gusA after hrpRS, hrpL, and a downstream effector gene, avrPto in the chromosome of Pst DC3000. I then analyzed GUS activity of each reporter strain cultured under variable conditions. I verified that repression of Pst DC3000 T3SS genes in KB acts upstream of the hrpRS operon, and that this repression is relieved by overexpression of either hrpR or hrpS. Furthermore, I demonstrated that hrpRS, hrpL, and avrPto, are differentially regulated by pH and carbon sources, although all carbon source tested (including sugars, a sugar alcohol, glycerol, and organic acids) initially induced T3SS gene expression. Results of several assays suggest that quorum sensing may be involved in regulation of the T3SS in Pst DC3000. First, T3SS genes were optimally expressed when growth media contained carbon sources that promoted slower growth, and when bacteria were cultured at low cell densities. In addition, I show that a T3SS repressive signal accumulated in high cell density Pst DC3000 cultures. However, density-dependent repression of T3SS genes was independent of psyRI, which mediates quorum sensing by acyl homoserine lactones (AHLs), and T3SS gene expression was unaffected by addition of 3-oxo-C6 or C6 AHLs. In contrast, T3SS genes were repressed when another small molecule produced by P. syringae, the auxin IAA, is added to Pst DC3000 cultures. However the biological relevance of IAA as a T3SS repressing signal remains to be explored.

Download or read book Recognition of Effectors by the Bacterial Type III Secretion System written by Loren E. Rodgers and published by . This book was released on 2008 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pathogenic bacteria possess virulence proteins which are exquisitely tuned to modulate an array of targets. The type III secretion (TTS) system is broadly utilized by Gram-negative bacteria to deliver these effectors into host cells. Yersinia pseudotuberculosis delivers six virulence proteins, called "Yops," into host cells. Yops modulate the inflammatory response, cell survival, and phagocytosis - effective tactics which enable the bacterium to colonize phagocyte-rich lymph nodes. YopE is particularly well-studied, and disables members of the Rho protein family, which are critical to phagocytosis through their modulation of the actin cytoskeleton. Like many TTS effectors, translocation of YopE into host cells requires its prior association with a dedicated chaperone protein within the bacterium. The mechanism by which this association promotes YopE translocation is the topic of this dissertation. I present evidence that SycE promotes a disorder-to-order transition within the chaperone-binding region of YopE. Among the secondary structure generated upon association between SycE and YopE is a [beta]-hairpin in YopE, and I hypothesize that the ordering of specific residues within this domain serves to target the effector to a component of the TTS system required for translocation. Structures of diverse TTS effectors from several species reveal that this motif is conserved, indicating that this motif might function as a general targeting motif. I mutated a set of three or five residues within the YopE [beta]-hairpin and find the translocation of the altered protein to be dramatically reduced. We demonstrate that these mutations do not destabilize the YopE-SycE interaction, and we propose that the ordering of these YopE residues by the chaperone SycE identifies the effector as a substrate for the TTS system. We seek to identify the receptor for this targeting signal, and we present preliminary results on purification of several proteins that might function as receptors for translocation targeting signals. Finally, recommendations are made for future investigations.

Download or read book Principles of Bacterial Pathogenesis written by Eduardo A. Groisman and published by Academic Press. This book was released on 2001-01-09 with total page 863 pages. Available in PDF, EPUB and Kindle. Book excerpt: Principles of Bacterial Pathogenesis presents a molecular perspective on a select group of bacterial pathogens by having the leaders of the field present their perspective in a clear and authoritative manner. Each chapter contains a comprehensive review devoted to a single pathogen. Several chapters include work from authors outside the pathogenesis field, providing general perspectives on the evolution, regulation, and secretion of virulence and determinants. Explains the basic principles of bacterial pathogenesis Covers diverse aspects integrating regulation, cellular microbiology and evolution of microbial disease of humans Discusses current strategies for the identification of virulence determinants and the methods used by microbes to deliver virulence factors Presents authoritative treatises of the major disease microorganisms

Download or read book Investigating the Evolution and Functional Diversification of Pseudomonas Syringae Type III Effector HopZ1 written by Carmen Yea and published by . This book was released on 2011 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt: The pathogenicity of plant pathogen Pseudomonas syringae depends on the type III secretion system which translocates effector proteins into host cells. In response, plants have evolved resistance proteins to detect presence of specific effectors and activate defense responses. The constant host surveillance imposes a strong selective pressure on effector proteins to evolve rapidly in order to evade detection. The P. syringae HopZ1 effector has evolved into three allelic forms as a result of diversifying selection. In this thesis, I aimed to investigate how sequence divergence contributes to the distinct allelic specificities of HopZ1. Mutational analysis of HopZ1a identified three amino acid residues that were potentially involved in dampening host defense responses, and two HopZ1a mutants partially lost the ability to trigger defense responses yet did not lose their virulence functions. These results suggested that distinct host targets could be involved in the defense-eliciting activity and virulence function of HopZ1a.