Isolation and Physical Mapping of the Gene Encoding the Major σ Factor of Bacillus subtilis RNA Polymerase
Abstract
At least four sigma factors separately bind the Bacillus subtilis RNA polymerase core (beta beta' alpha 2), each conferring a different promoter specificity on the holoenzyme in vitro. Using the Broome-Gilbert immunological screening, we isolated recombinant lambda phages that carry rpoD, the gene for the most abundant sigma factor, sigma 55. These phages encode a 55,000-dalton protein whose size, immunological properties, and peptide map identify it as sigma 55. All the phages have in common two adjacent 3.5-kilobase EcoRI fragments from the B. subtilis chromosome; most carry additional genomic DNA. Deletion analysis localized rpoD to a 1.6-kilobase region, suggested the direction of its transcription, and found two additional genes near rpoD, which code for proteins of 62,000 and 17,000 daltons.
- Publication:
-
Proceedings of the National Academy of Science
- Pub Date:
- July 1983
- DOI:
- 10.1073/pnas.80.13.4074
- Bibcode:
- 1983PNAS...80.4074P