title: Virulence attenuation in Salmonella enterica rcsC mutants with constitutive activation of the Rcs system.
abstract: Mutations in rcsC that result in constitutive colanic acid capsule synthesis were obtained in Salmonella enterica serovar Typhimurium. Most rcsC alleles were dominant; however, recessive rcsC alleles were also found, in agreement with the postulated double role (positive and negative) of RcsC on the activation of the RcsB/C phosphorelay system. Salmonella rcsC mutants with constitutive activation of the Rcs system are severely attenuated for virulence in BALB/c mice and their degree of attenuation correlates with the level of Rcs activation. Partial relief of attenuation by a gmm mutation indicates that capsule overproduction is one of the factors leading to avirulence in constitutively activated rcsC mutants.
authors.affiliation: Departamento de Genética, Facultad de Biología, Universidad de Sevilla, Apartado 1095, 41080 Sevilla, Spain.
authors.forename: Clara B
authors.initials: CB
authors.lastname: García-Calderón
authors.affiliation: Departamento de Genética, Facultad de Biología, Universidad de Sevilla, Apartado 1095, 41080 Sevilla, Spain.
authors.forename: Meritxell
authors.initials: M
authors.lastname: García-Quintanilla
authors.affiliation: Departamento de Genética, Facultad de Biología, Universidad de Sevilla, Apartado 1095, 41080 Sevilla, Spain.
authors.forename: Josep
authors.initials: J
authors.lastname: Casadesús
authors.affiliation: Departamento de Genética, Facultad de Biología, Universidad de Sevilla, Apartado 1095, 41080 Sevilla, Spain.
authors.forename: Francisco
authors.initials: F
authors.lastname: Ramos-Morales
mesh_terms: D000818:Animals; D016667:Bacterial Capsules / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism; D005260:Female; D015964:Gene Expression Regulation, Bacterial; D051379:Mice; D008807:Mice, Inbred BALB C; D009097:Multienzyme Complexes / Q000235:genetics* / Q000378:metabolism; D009154:Mutation; D010749:Phosphoprotein Phosphatases / Q000235:genetics* / Q000378:metabolism; D011134:Polysaccharides / Q000378:metabolism; D011494:Protein Kinases / Q000235:genetics* / Q000378:metabolism; D012480:Salmonella Infections / Q000382:microbiology; D012486:Salmonella typhimurium / Q000235:genetics / Q000378:metabolism / Q000472:pathogenicity*; D014157:Transcription Factors / Q000235:genetics; D014774:Virulence
chemical_list: D001426:Bacterial Proteins; D009097:Multienzyme Complexes; D011134:Polysaccharides; D014157:Transcription Factors; C074889:RcsB protein, Bacteria; C004275:colanic acid; D011494:Protein Kinases; D010749:Phosphoprotein Phosphatases