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Application of Biolayer Interferometry (BLI) for Studying Protein-Protein Interactions in Transcription
Published on: July 26, 2019
Selective promoter recognition by chlamydial sigma28 holoenzyme
Li Shen1, Xiaogeng Feng, Yuan Yuan
1Department of Medicine, Boston Medical Center, Boston University School of Medicine, MA 02118, USA. lshen@bu.edu
Journal of Bacteriology
|August 29, 2006
Summary
Chlamydia trachomatis sigma(28) (sigma(28)(Ct)) recognizes specific bacterial promoters. This sigma factor shows flexibility in promoter recognition, differing from E. coli sigma(28) (sigma(28)(Ec)).
Area of Science:
- Microbiology
- Molecular Biology
- Genetics
Background:
- Sigma transcription factors regulate promoter specificity for RNA polymerase (RNAP) in bacteria.
- Chlamydia trachomatis possesses three known sigma factors, including sigma(28).
Purpose of the Study:
- To characterize promoter sequences recognized by Chlamydia trachomatis sigma(28) (sigma(28)(Ct)).
- To compare the promoter recognition properties of sigma(28)(Ct) with E. coli sigma(28) (sigma(28)(Ec)).
Main Methods:
- Developed two methods for characterizing sigma(28)(Ct) promoter recognition.
- Utilized arabinose-induced expression in a modified E. coli strain.
- Performed in vitro transcription assays with reconstituted hybrid holoenzymes.
Main Results:
- RNAP with sigma(28)(Ct) recognizes some, but not all, sigma(28)(Ec)-dependent promoters.
- sigma(28)(Ct) preferentially activates promoters with upstream AT-rich sequences.
- sigma(28)(Ct) exhibits greater flexibility in recognizing promoter variants with altered spacing between -35 and -10 elements compared to sigma(28)(Ec).
Conclusions:
- Sigma(28)(Ct) possesses distinct promoter recognition capabilities compared to sigma(28)(Ec).
- The study provides insights into the promoter specificity of a key Chlamydia trachomatis transcription factor.
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