A Bacillus-specific factor is needed to trigger the stress-activated phosphatase/kinase cascade of sigmaB induction.
The general stress regulon of Bacillus subtilis is controlled by the transcription factor sigmaB. Environmental stress activates sigmaB via a phosphatase/kinase cascade that triggers sigmaB's release from an anti sigma factor complex. To determine if the members of the phosphatase/kinase cascade are sufficient to detect environmental stress and activate sigmaB, we expressed sigmaB and its regulators in E. coli. In E. coli, as in B. subtilis, the intact collection of regulators silenced sigmaB, while allowing sigmaB to be active if the cascade's most upstream negative regulator was deleted. The regulators could not, however, activate sigmaB in response to ethanol treatment or heat shock. In other experiments, the GroEL and DnaK chaperones, known to be important in controlling stress sigma factors in E. coli, were found to be unimportant for sigmaB activity in B. subtilis. The findings argue that stress induction of sigmaB requires novel factors that are B. subtilis specific.
Scott
J M
JM
Department of Microbiology, University of Texas Health Science Center at San Antonio, San Antonio, Texas 78284-7758, USA.
Smirnova
N
N
Haldenwang
W G
WG
D049069:ATP-Dependent Proteases; D001412:Bacillus subtilis / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D001685:Biological Factors / Q000502:physiology*; D015153:Blotting, Western; D018834:Chaperonin 60 / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D029968:Escherichia coli Proteins; D000431:Ethanol / Q000494:pharmacology; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects; D017930:Genes, Reporter; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism; D006360:Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism; D018869:Heat-Shock Response / Q000235:genetics; D009154:Mutation; D009876:Operon / Q000235:genetics; D010744:Phosphoric Monoester Hydrolases / Q000378:metabolism*; D010770:Phosphotransferases / Q000378:metabolism*; D011401:Promoter Regions, Genetic / Q000235:genetics; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D012697:Serine Endopeptidases / Q000235:genetics / Q000378:metabolism; D012808:Sigma Factor / Q000235:genetics / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects
D001426:Bacterial Proteins; D001685:Biological Factors; D018834:Chaperonin 60; D029968:Escherichia coli Proteins; D018840:HSP70 Heat-Shock Proteins; D006360:Heat-Shock Proteins; D011994:Recombinant Proteins; C079011:SigB protein, Bacteria; D012808:Sigma Factor; D000431:Ethanol; D010770:Phosphotransferases; D010744:Phosphoric Monoester Hydrolases; D049069:ATP-Dependent Proteases; D012697:Serine Endopeptidases; C063842:dnaK protein, E coli