Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

The effect of stpA deletion on S. Typhimurium gene expression during growth in rich medium

ABSTRACT: StpA is a paralogue of the nucleoid associated protein H-NS that is conserved in a range of enteric bacteria and had no known function in Salmonella enterica serovar Typhimurium. Here, we show that 5% of the Salmonella genome is regulated by StpA, which contrasts with the situation in Escherichia coli where deletion of stpA only had minor effects on gene expression. The StpA-dependent genes of S. Typhimurium are a specific subset of the H-NS regulon that are predominantly under the positive control of sigma38 (RpoS), CRP-cAMP and PhoP. The regulatory role of StpA varied at different growth phases; StpA only controlled sigma38 levels at mid-exponential phase when it prevented inappropriate activation of sigma38 during rapid bacterial growth. In contrast, StpA only activated the CRP-cAMP regulon during late exponential phase. The effect of stpA deletion on S. Typhimurium gene expression during growth in LB was analysed at 4 different time points (early-log, mid-log, late-log, and stationary phase) where the gene expression profile of the stpA-deletion strain was compared to that of the parental strain. Between two and three biological replicates were performed for each strain and time point. For this study, we used Salmonella genomic DNA as the comparator which also acted as the control for spot quality.

ORGANISM(S): Salmonella typhimurium SL1344

SUBMITTER: Sacha Lucchini

PROVIDER: E-GEOD-18424 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Publications

The H-NS-like protein StpA represses the RpoS (sigma 38) regulon during exponential growth of Salmonella Typhimurium.

Lucchini Sacha S McDermott Paul P Thompson Arthur A Hinton Jay C D JC

Molecular microbiology 20091019 5

StpA is a paralogue of the nucleoid-associated protein H-NS that is conserved in a range of enteric bacteria and had no known function in Salmonella Typhimurium. We show that 5% of the Salmonella genome is regulated by StpA, which contrasts with the situation in Escherichia coli where deletion of stpA only had minor effects on gene expression. The StpA-dependent genes of S. Typhimurium are a specific subset of the H-NS regulon that are predominantly under the positive control of sigma(38) (RpoS) ...[more]

PMID: 19843227

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Dataset Information

The effect of stpA deletion on S. Typhimurium gene expression during growth in rich medium

Publications

The H-NS-like protein StpA represses the RpoS (sigma 38) regulon during exponential growth of Salmonella Typhimurium.

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