title: Isolation and physical mapping of the gene encoding the major sigma 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.
mesh_terms: D001412:Bacillus subtilis / Q000201:enzymology* / Q000235:genetics; D010582:Bacteriophage lambda / Q000235:genetics; D004262:DNA Restriction Enzymes; D004926:Escherichia coli / Q000235:genetics; D005796:Genes; D005798:Genes, Bacterial; D008970:Molecular Weight; D012234:Rho Factor / Q000235:genetics* / Q000302:isolation & purification; D014157:Transcription Factors / Q000235:genetics*
chemical_list: D012234:Rho Factor; D014157:Transcription Factors; D004262:DNA Restriction Enzymes