This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrowReprints and Permissions
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Chander, M.
Right arrow Articles by Demple, B.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Chander, M.
Right arrow Articles by Demple, B.

 Previous Article  |  Next Article 

Journal of Bacteriology, April 2003, p. 2441-2450, Vol. 185, No. 8
0021-9193/03/$08.00+0     DOI: 10.1128/JB.185.8.2441-2450.2003
Copyright © 2003, American Society for Microbiology. All Rights Reserved.

Transcription-Defective soxR Mutants of Escherichia coli: Isolation and In Vivo Characterization

Monica Chander, Laura Raducha-Grace, and Bruce Demple*

Department of Cancer Cell Biology, Harvard School of Public Health, Boston, Massachusetts 02115

Received 31 October 2002/ Accepted 28 January 2003

The soxRS regulon protects Escherichia coli from superoxide and nitric oxide stress. SoxR protein, a transcription factor that senses oxidative stress via its [2Fe-2S] centers, transduces the signal to the soxS promoter to stimulate RNA polymerase. Here we describe 29 mutant alleles of soxR that cause defects in the activation of soxS transcription in response to paraquat, a superoxide stress agent. Owing to the selection and screen used in their isolation, most of these mutant alleles encode proteins that retained specific binding activity for the soxS promoter in vivo. The mutations were found throughout the SoxR polypeptide, although those closer to the N terminus typically exhibited greater defects in DNA binding. The degree of the defect in the transcriptional response to superoxide caused by each mutation was closely paralleled by its impaired response to nitric oxide. This work begins the general identification of the residues in the SoxR polypeptide that are critical for transducing oxidative stress signals into gene activation.

* Corresponding author. Mailing address: Department of Cancer Cell Biology, Harvard School of Public Health, 665 Huntington Ave., Boston, MA 02115. Phone: (617) 432-3462. Fax: (617) 432-2590. E-mail: bdemple{at}hsph.harvard.edu.

Journal of Bacteriology, April 2003, p. 2441-2450, Vol. 185, No. 8
0021-9193/03/$08.00+0     DOI: 10.1128/JB.185.8.2441-2450.2003
Copyright © 2003, American Society for Microbiology. All Rights Reserved.



This article has been cited by other articles:

  • Watanabe, S., Kita, A., Kobayashi, K., Miki, K. (2008). Crystal structure of the [2Fe-2S] oxidative-stress sensor SoxR bound to DNA. Proc. Natl. Acad. Sci. USA 105: 4121-4126 [Abstract] [Full Text]  
  • Giro, M., Carrillo, N., Krapp, A. R. (2006). Glucose-6-phosphate dehydrogenase and ferredoxin-NADP(H) reductase contribute to damage repair during the soxRS response of Escherichia coli.. Microbiology 152: 1119-1128 [Abstract] [Full Text]  
  • Chander, M., Demple, B. (2004). Functional Analysis of SoxR Residues Affecting Transduction of Oxidative Stress Signals into Gene Expression. J. Biol. Chem. 279: 41603-41610 [Abstract] [Full Text]  


Copyright © 2009 by the American Society for Microbiology.   For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»