Related Experiment Videos
Sequence specificity for DNA binding by Escherichia coli SoxS and Rob proteins
1Department of Molecular and Cellular Toxicology, Harvard School of Public Health, Boston, Massachusetts 02115, USA.
Molecular Microbiology
|June 1, 1996
Summary
The SoxS transcriptional activator in E. coli binds to oxidative stress gene promoters. Researchers identified a consensus DNA binding sequence for SoxS, aiding in the discovery of new regulated genes.
Area of Science:
- Microbiology
- Molecular Biology
- Genetics
Background:
- SoxS is a transcriptional activator of oxidative stress genes in Escherichia coli.
- The Rob protein shares sequence identity with SoxS and binds similar promoters.
Purpose of the Study:
- To elucidate the binding mechanism and sequence specificity of SoxS.
- To identify potential new SoxS-regulated genes in E. coli.
Main Methods:
- In vitro DNA-binding assays using SoxS and Rob.
- Methylation interference assays to identify key binding residues.
- Analysis of mutated oligonucleotides and published DNase I footprinting data.
- Bioinformatic search for SoxS binding sites in the E. coli genome.
Main Results:
- SoxS forms multiple complexes with promoters due to multiple binding sites.
- A consensus DNA binding sequence for SoxS (AN2GCAYN7CWA) was determined.
- Sequence requirements for Rob binding differ from SoxS.
- Several potentially SoxS-regulated genes were identified.
Conclusions:
- The study defines the sequence specificity of SoxS binding.
- Identified genes may play roles in cellular oxidative stress resistance.
- Provides a foundation for understanding the soxRS regulon in E. coli.