Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

Time course of manganese treatment in LB

ABSTRACT: The SOS response to DNA damage in bacteria is a well-known component of the complex transcriptional responses to genotoxic environmental stresses such as exposure to reactive oxygen species, alkylating agents, and many of the antibiotics targeting DNA replication. However, bacteria such as Bacillus subtilis also respond to conditions that perturb DNA replication via a transcriptional response mediated by the replication initiation protein DnaA. In addition to regulating the initiation of DNA replication, DnaA directly regulates the transcription of specific genes. Conditions that perturb DNA replication can trigger the accumulation of active DnaA, activating or repressing transcription of genes in the DnaA regulon. We report here that simply growing B. subtilis in LB medium altered DnaA-dependent gene expression in a manner consistent with the accumulation of active DnaA, and that this was part of a general transcriptional response to manganese limitation. The SOS response to DNA damage was not induced under these conditions. One of the genes positively regulated by DnaA in Bacillus subtilis encodes a protein that inhibits the initiation of sporulation, Sda. Sda expression was induced as cells entered stationary phase in LB but not in LB supplemented with manganese, and induction of Sda inhibited sporulation-specific gene expression and the onset of spore morphogenesis. In the absence of Sda, manganese-limited cells initiated spore development but failed to form mature spores. These data highlight that DnaA-dependent gene expression may influence the response of bacteria to a range of environmental conditions, including conditions that are not obviously associated with genotoxic stress. Cultures of Bacillus subtilis strains with the genetic background of sda+ or delta-sda were grown in LB and LB+100 micro-M MnCl2 at 37degC until 3 hours after the onset of stationary phase. At 3 timepoints, aliqots were removed and RNA isolated for each culture: 1) Mid exponential, 2) T0 (onset of stationary phase), and 3) T3 (3 hours after onset of stationary phase). cDNA was prepared from each sample using 10 micro-g of RNA. Reference cDNA was prepared from pooled RNA from all samples (common reference for all arrays).

ORGANISM(S): Bacillus subtilis

SUBMITTER: Sharon Hoover

PROVIDER: E-GEOD-22296 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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Changes in DnaA-dependent gene expression contribute to the transcriptional and developmental response of Bacillus subtilis to manganese limitation in Luria-Bertani medium.

Hoover Sharon E SE Xu Weihong W Xiao Wenzhong W Burkholder William F WF

Journal of bacteriology 20100528 15

The SOS response to DNA damage in bacteria is a well-known component of the complex transcriptional responses to genotoxic environmental stresses such as exposure to reactive oxygen species, alkylating agents, and many of the antibiotics targeting DNA replication. However, bacteria such as Bacillus subtilis also respond to conditions that perturb DNA replication via a transcriptional response mediated by the replication initiation protein DnaA. In addition to regulating the initiation of DNA rep ...[more]

PMID: 20511500

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Dataset Information

Time course of manganese treatment in LB

Publications

Changes in DnaA-dependent gene expression contribute to the transcriptional and developmental response of Bacillus subtilis to manganese limitation in Luria-Bertani medium.

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