Unknown,Transcriptomics,Genomics,Proteomics

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Bacillus Stress Responses

ABSTRACT: Bacillus subtilis exhibits a complex adaptive response to low levels of peroxides. We used global transcriptional profiling to monitor the magnitude and kinetics of changes in the mRNA population after exposure to either hydrogen peroxide (H2O2) or tert-butyl peroxide (t-buOOH). The peroxide stimulons could be largely accounted for by three regulons controlled by the PerR, B, and OhrR transcription factors. Three members of the PerR regulon (katA, mrgA, and zosA) were strongly induced by H2O2 and weakly induced by t-buOOH. The remaining members of the PerR regulon were only modestly up-regulated by peroxide treatment. Overall, the magnitude of peroxide induction of PerR regulon genes corresponded well with the extent of derepression in a perR mutant strain. The B regulon was activated by 58 ÂµM H2O2 but not by 8 ÂµM H2O2 and was strongly activated by either t-buOOH or, in a control experiment, tert-butyl alcohol. Apart from the B regulon there was a single gene, ohrA, that was strongly and rapidly induced by t-buOOH exposure. This gene, controlled by the peroxide-sensing repressor OhrR, was not induced by any of the other conditions tested. Set of arrays organized by shared biological context, such as organism, tumors types, processes, etc. Computed

ORGANISM(S): Bacillus subtilis

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PROVIDER: E-GEOD-3138 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

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The global transcriptional response of Bacillus subtilis to peroxide stress is coordinated by three transcription factors.

Helmann John D JD Wu Ming Fang Winston MF Gaballa Ahmed A Kobel Phil A PA Morshedi Maud M MM Fawcett Paul P Paddon Chris C

Journal of bacteriology 20030101 1

Bacillus subtilis exhibits a complex adaptive response to low levels of peroxides. We used global transcriptional profiling to monitor the magnitude and kinetics of changes in the mRNA population after exposure to either hydrogen peroxide (H(2)O(2)) or tert-butyl peroxide (t-buOOH). The peroxide stimulons could be largely accounted for by three regulons controlled by the PerR, sigma(B), and OhrR transcription factors. Three members of the PerR regulon (katA, mrgA, and zosA) were strongly induced ...[more]

PMID: 12486061

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Dataset Information

Bacillus Stress Responses

Publications

The global transcriptional response of Bacillus subtilis to peroxide stress is coordinated by three transcription factors.

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