title: The GATC-binding protein SeqA is required for bile resistance and virulence in Salmonella enterica serovar typhimurium.
abstract: Disruption of the seqA gene of Salmonella enterica serovar Typhimurium causes defects similar to those described in E. coli: filament formation, aberrant nucleoid segregation, induction of the SOS response, envelope instability, and increased sensitivity to membrane-damaging agents. Differences between SeqA(-) mutants of E. coli and S. enterica, however, are found. SeqA(-) mutants of S. enterica form normal colonies and do not exhibit alterations in phage plaquing morphology. Lack of SeqA causes attenuation of S. enterica virulence by the oral route but not by the intraperitoneal route, suggesting a virulence defect in the intestinal stage of infection. However, SeqA(-) mutants are fully proficient in the invasion of epithelial cells. We hypothesize that attenuation of SeqA(-) mutants by the oral route may be caused by bile sensitivity, which in turn may be a consequence of envelope instability.
authors: Departamento de Genética, Facultad de Biología, Universidad de Sevilla, Apartado 1095, Sevilla 41080, Spain.
authors: Ana I
authors: AI
authors: Prieto
authors: Marcello
authors: M
authors: Jakomin
authors: Ignacio
authors: I
authors: Segura
authors: M Graciela
authors: MG
authors: Pucciarelli
authors: Francisco
authors: F
authors: Ramos-Morales
authors: Francisco
authors: F
authors: García-Del Portillo
authors: Josep
authors: J
authors: Casadesús
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001483:Base Sequence; D001646:Bile / Q000502:physiology*; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D024881:Drug Resistance, Bacterial; D000431:Ethanol / Q000494:pharmacology; D017353:Gene Deletion; D006367:HeLa Cells; D006801:Humans; D008826:Microbial Sensitivity Tests; D012486:Salmonella typhimurium / Q000187:drug effects / Q000235:genetics / Q000378:metabolism* / Q000472:pathogenicity*; D014774:Virulence
chemical_list: D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D000431:Ethanol