title: Global regulation in Erwinia species by Erwinia carotovora rsmA, a homologue of Escherichia coli csrA: repression of secondary metabolites, pathogenicity and hypersensitive reaction.
abstract: Our previous studies revealed that rsmA of Erwinia carotovora subsp. carotovora strain 71 suppressed the synthesis of the cell density (quorum) sensing signal N-(3-oxohexanoyl)-L-homoserine lactone, the production of extracellular enzymes and tissue macerating ability in soft-rotting Erwinia species and that homologues of this negative regulator gene were present in other Erwinia species. Northern blot data presented here demonstrate that rsmA and rsmA-like genes are also expressed in soft-rotting and non-soft-rotting Erwinia spp. such as E. amylovora, E. carotovora subsp. atroseptica, E. carotovora subsp. betavasculorum, E. carotovora subsp. carotovora, E. chrysanthemi, E. herbicola and E. stewartii. A low-copy plasmid carrying rsmA of E. carotovora subsp. carotovora strain 71 caused suppression of antibiotic production in E. carotovora subsp. betavasculorum, flagellum formation in E. carotovora subsp. carotovora, carotenoid production in E. herbicola and E. stewartii, and indigoidine production in E. chrysanthemi. In E. amylovora, rsmA of E. carotovora subsp. carotovora suppressed the elicitation of the hypersensitive reaction in tobacco leaves and the production of disease symptoms in apple shoots, in addition to repressing motility and extracellular polysaccharide production. We conclude that rsmA homologues function as global regulators of secondary metabolic pathways as well as factors controlling host interaction of Erwinia species.
authors.affiliation: Department of Plant Pathology, University of Missouri, Columbia, MO 65211, USA.
authors.forename: Asita
authors.initials: A
authors.lastname: Mukherjee
authors.affiliation: Department of Plant Pathology, University of Missouri, Columbia, MO 65211, USA.
authors.forename: Yaya
authors.initials: Y
authors.lastname: Cui
authors.affiliation: Department of Plant Pathology, University of Missouri, Columbia, MO 65211, USA.
authors.forename: Yang
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Plant Pathology, University of Missouri, Columbia, MO 65211, USA.
authors.forename: C Korsi
authors.initials: CK
authors.lastname: Dumenyo
authors.affiliation: Department of Plant Pathology, University of Missouri, Columbia, MO 65211, USA.
authors.forename: Arun K
authors.initials: AK
authors.lastname: Chatterjee
mesh_terms: D000900:Anti-Bacterial Agents / Q000096:biosynthesis; D002338:Carotenoids / Q000096:biosynthesis; D004926:Escherichia coli / Q000235:genetics*; D005798:Genes, Bacterial; D005809:Genes, Regulator; D016973:Pectobacterium carotovorum / Q000235:genetics* / Q000378:metabolism / Q000472:pathogenicity; D010935:Plant Diseases / Q000209:etiology; D011135:Polysaccharides, Bacterial / Q000096:biosynthesis; D012329:RNA, Bacterial / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D013045:Species Specificity; D014774:Virulence / Q000235:genetics
chemical_list: D000900:Anti-Bacterial Agents; D011135:Polysaccharides, Bacterial; D012329:RNA, Bacterial; D012333:RNA, Messenger; D002338:Carotenoids