title: The Salmonella effector protein SpvC, a phosphothreonine lyase is functional in plant cells.
abstract: Salmonella is one of the most prominent causes of food poisoning and growing evidence indicates that contaminated fruits and vegetables are an increasing concern for human health. Successful infection demands the suppression of the host immune system, which is often achieved via injection of bacterial effector proteins into host cells. In this report we present the function of Salmonella effector protein in plant cell, supporting the new concept of trans-kingdom competence of this bacterium. We screened a range of Salmonella Typhimurium effector proteins for interference with plant immunity. Among these, the phosphothreonine lyase SpvC attenuated the induction of immunity-related genes when present in plant cells. Using in vitro and in vivo systems we show that this effector protein interacts with and dephosphorylates activated Arabidopsis Mitogen-activated Protein Kinase 6 (MPK6), thereby inhibiting defense signaling. Moreover, the requirement of Salmonella SpvC was shown by the decreased proliferation of the ΔspvC mutant in Arabidopsis plants. These results suggest that some Salmonella effector proteins could have a conserved function during proliferation in different hosts. The fact that Salmonella and other Enterobacteriaceae use plants as hosts strongly suggests that plants represent a much larger reservoir for animal pathogens than so far estimated.
authors.affiliation: Research Center for BioSystems, Land Use and Nutrition, Institute for Phytopathology and Applied Zoology, Justus-Liebig University Giessen Giessen, Germany.
authors.forename: Christina
authors.initials: C
authors.lastname: Neumann
authors.affiliation: Department of Plant Biochemistry, Center for Plant Molecular Biology (ZMBP), Eberhard Karls University Tübingen Tübingen, Germany.
authors.forename: Malou
authors.initials: M
authors.lastname: Fraiture
authors.affiliation: Research Center for BioSystems, Land Use and Nutrition, Institute for Phytopathology and Applied Zoology, Justus-Liebig University Giessen Giessen, Germany.
authors.forename: Casandra
authors.initials: C
authors.lastname: Hernàndez-Reyes
authors.affiliation: Research Center for BioSystems, Land Use and Nutrition, Institute for Phytopathology and Applied Zoology, Justus-Liebig University Giessen Giessen, Germany.
authors.forename: Fidele N
authors.initials: FN
authors.lastname: Akum
authors.affiliation: Institut National de la Recherche Agronomique, UMR1282 Infectiologie et Santé Publique Nouzilly, France ; Université François Rabelais de Tours, UMR1282 Infectiologie et Santé Publique Tours, France.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Virlogeux-Payant
authors.affiliation: Department of Plant Biochemistry, Center for Plant Molecular Biology (ZMBP), Eberhard Karls University Tübingen Tübingen, Germany.
authors.forename: Ying
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Unité de Recherche en Génomique Végétale, Plant Genomics Evry, France.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Pateyron
authors.affiliation: Unité de Recherche en Génomique Végétale, Plant Genomics Evry, France.
authors.forename: Jean
authors.initials: J
authors.lastname: Colcombet
authors.affiliation: Research Center for BioSystems, Land Use and Nutrition, Institute for Phytopathology and Applied Zoology, Justus-Liebig University Giessen Giessen, Germany.
authors.forename: Karl-Heinz
authors.initials: KH
authors.lastname: Kogel
authors.affiliation: Unité de Recherche en Génomique Végétale, Plant Genomics Evry, France.
authors.forename: Heribert
authors.initials: H
authors.lastname: Hirt
authors.affiliation: Department of Plant Biochemistry, Center for Plant Molecular Biology (ZMBP), Eberhard Karls University Tübingen Tübingen, Germany.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Brunner
authors.affiliation: Research Center for BioSystems, Land Use and Nutrition, Institute for Phytopathology and Applied Zoology, Justus-Liebig University Giessen Giessen, Germany.
authors.forename: Adam
authors.initials: A
authors.lastname: Schikora
keywords: Salmonella; T3SS; plant infection; trans-kingdom pathogenicity