Dataset Information

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.

SUBMITTER: Prieto AI

PROVIDER: S-EPMC2168936 | biostudies-literature | 2007 Dec

REPOSITORIES: biostudies-literature

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The GATC-binding protein SeqA is required for bile resistance and virulence in Salmonella enterica serovar typhimurium.

Prieto Ana I AI Jakomin Marcello M Segura Ignacio I Pucciarelli M Graciela MG Ramos-Morales Francisco F García-Del Portillo Francisco F Casadesús Josep J

Journal of bacteriology 20070928 23

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 ...[more]

PMID: 17905993

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Dataset Information

The GATC-binding protein SeqA is required for bile resistance and virulence in Salmonella enterica serovar typhimurium.

Publications

The GATC-binding protein SeqA is required for bile resistance and virulence in Salmonella enterica serovar typhimurium.

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