title: Chromosomal locus that affects pathogenicity of Rhodococcus fascians.
abstract: The gram-positive plant pathogen Rhodococcus fascians provokes leafy gall formation on a wide range of plants through secretion of signal molecules that interfere with the hormone balance of the host. Crucial virulence genes are located on a linear plasmid, and their expression is tightly controlled. A mutant with a mutation in a chromosomal locus that affected virulence was isolated. The mutation was located in gene vicA, which encodes a malate synthase and is functional in the glyoxylate shunt of the Krebs cycle. VicA is required for efficient in planta growth in symptomatic, but not in normal, plant tissue, indicating that the metabolic requirement of the bacteria or the nutritional environment in plants or both change during the interaction. We propose that induced hyperplasia on plants represents specific niches for the causative organisms as a result of physiological alterations in the symptomatic tissue. Hence, such interaction could be referred to as metabolic habitat modification.
authors.affiliation: Vakgroep Moleculaire Genetica, Departement Plantengenetica, Vlaams Interuniversitair Instituut voor Biotechnologie, Universiteit Gent, B-9000 Ghent, Belgium.
authors.forename: Danny
authors.initials: D
authors.lastname: Vereecke
authors.forename: Karen
authors.initials: K
authors.lastname: Cornelis
authors.forename: Wim
authors.initials: W
authors.lastname: Temmerman
authors.forename: Mondher
authors.initials: M
authors.lastname: Jaziri
authors.forename: Marc
authors.initials: M
authors.lastname: Van Montagu
authors.forename: Marcelle
authors.initials: M
authors.lastname: Holsters
authors.forename: Koen
authors.initials: K
authors.lastname: Goethals
mesh_terms: D001483:Base Sequence; D002244:Carbon; D002876:Chromosomes, Bacterial; D004269:DNA, Bacterial; D005786:Gene Expression Regulation; D005798:Genes, Bacterial; D006038:Glyoxylates / Q000378:metabolism; D008292:Malate Synthase / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D012240:Rhodococcus / Q000235:genetics* / Q000472:pathogenicity; D017422:Sequence Analysis, DNA; D014774:Virulence
chemical_list: D004269:DNA, Bacterial; D006038:Glyoxylates; D002244:Carbon; D008292:Malate Synthase; C031150:glyoxylic acid