title: Isolation of sigma-28-specific promoters from Bacillus subtilis DNA.
abstract: Sigma-28-RNA polymerase is a minor form of RNA polymerase found in vegetative cells of Bacillus subtilis which utilizes promoter sites distinct from those recognized by the major RNA polymerase. We have isolated a collection of cloned B. subtilis DNA segments that contain in vitro promoter sites for sigma 28-RNA polymerase by screening a bacteriophage lambda library of B. subtilis genomic fragments. At least nine new sigma 28-specific promoter sites have been identified in this collection, and four have been partially mapped for further study. Our strategy employed a mix of RNA probes prepared by in vitro transcription with sigma 28-RNA polymerase of total B. subtilis DNA EcoRI and HindIII fragments. Over 70% of the unique clones identified contain sigma 28-specific promoter sites, suggesting that the method may have general application for identification of promoter-containing sequences. The efficiency with which sigma 28-specific promoters are detected is consistent with there being a relatively small number of such sites in the B. subtilis genome of which twelve have been cloned.
mesh_terms: D001412:Bacillus subtilis / Q000201:enzymology / Q000235:genetics*; D001426:Bacterial Proteins / Q000378:metabolism; D010582:Bacteriophage lambda / Q000235:genetics; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000235:genetics* / Q000378:metabolism; D005798:Genes, Bacterial; D011401:Promoter Regions, Genetic; D012808:Sigma Factor / Q000378:metabolism; D014158:Transcription, Genetic
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D012808:Sigma Factor