TY - JOUR
T1 - Transcription from the P3 promoter of the Bacillus subtilis spx gene is induced in response to bisulfide stress
AU - Leelakriangsak, Montira
AU - Zuber, Peter
PY - 2007/3
Y1 - 2007/3
N2 - The spx gene of Bacillus subtilis encodes a global regulator that controls transcription initiation in response to oxidative stress by interaction with RNA polymerase (RNAP). It is located in a dicistronic operon with the yjbC gene. The spx gene DNA complements an spx null mutation with respect to disulfide stress resistance, suggesting that spx is transcribed from a promoter located in the intergenic region oiyjbC and spx. Transcription of the yjbC-spx operon has been reported to be driven by four promoters, three (P1, P 2, and PB) residing upstream of yjbC and one (P M) located in the intergenic region between yjbC and spx. Primer extension analysis uncovered a second intergenic promoter, P3, from which transcription is elevated in cells treated with the thiol-specific oxidant diamide. P3 is utilized by the σAform of RNA polymerase in vitro without the involvement of a transcriptional activator. Transcriptional induction from P3 did not require an Spx-RNAP interaction and was observed in a deletion mutant lacking DNA upstream of position -40 of the P3 promoter start site. Deletion mutants with endpoints 3′ to the P3 transcriptional start site (positions +5, +15, and +30) showed near-constitutive transcription at the induced level, indicating the presence of a negative control element downstream of the P 3 promoter sequence. Point mutations characterized by bgaB fusion expression and primer extension analyses uncovered evidence for a second as-acting site in the P3 promoter sequence itself. The data indicate that spx transcription is under negative transcriptional control that is reversed when disulfide stress is encountered.
AB - The spx gene of Bacillus subtilis encodes a global regulator that controls transcription initiation in response to oxidative stress by interaction with RNA polymerase (RNAP). It is located in a dicistronic operon with the yjbC gene. The spx gene DNA complements an spx null mutation with respect to disulfide stress resistance, suggesting that spx is transcribed from a promoter located in the intergenic region oiyjbC and spx. Transcription of the yjbC-spx operon has been reported to be driven by four promoters, three (P1, P 2, and PB) residing upstream of yjbC and one (P M) located in the intergenic region between yjbC and spx. Primer extension analysis uncovered a second intergenic promoter, P3, from which transcription is elevated in cells treated with the thiol-specific oxidant diamide. P3 is utilized by the σAform of RNA polymerase in vitro without the involvement of a transcriptional activator. Transcriptional induction from P3 did not require an Spx-RNAP interaction and was observed in a deletion mutant lacking DNA upstream of position -40 of the P3 promoter start site. Deletion mutants with endpoints 3′ to the P3 transcriptional start site (positions +5, +15, and +30) showed near-constitutive transcription at the induced level, indicating the presence of a negative control element downstream of the P 3 promoter sequence. Point mutations characterized by bgaB fusion expression and primer extension analyses uncovered evidence for a second as-acting site in the P3 promoter sequence itself. The data indicate that spx transcription is under negative transcriptional control that is reversed when disulfide stress is encountered.
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U2 - 10.1128/JB.01519-06
DO - 10.1128/JB.01519-06
M3 - Article
C2 - 17158663
AN - SCOPUS:33947420461
SN - 0021-9193
VL - 189
SP - 1727
EP - 1735
JO - Journal of bacteriology
JF - Journal of bacteriology
IS - 5
ER -