title: Site-directed mutagenesis of a catabolite repression operator sequence in Bacillus subtilis.
abstract: Catabolite repression of the Bacillus subtilis alpha-amylase gene (amyE) involves an operator sequence located just downstream of the promoter (amyR), overlapping the transcription start site. Oligonucleotide site-directed mutagenesis of this sequence identified bases required for catabolite repression. Two mutations increased both the 2-fold symmetry of the operator and the repression ratio. Although many mutations reduced the repression ratio 3- to 11-fold, some also caused a 2-fold or greater increase in amylase production. Others caused hyperproduction without affecting catabolite repression. Homologous sequences in other catabolite-repressed B. subtilis promoters suggest a common regulatory site may be involved in catabolite repression.
authors.affiliation: Department of Genetics, University of Wisconsin, Madison 53706.
authors.forename: M J
authors.initials: MJ
authors.lastname: Weickert
authors.forename: G H
authors.initials: GH
authors.lastname: Chambliss
mesh_terms: D001412:Bacillus subtilis / Q000235:genetics*; D001483:Base Sequence; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000235:genetics; D004794:Enzyme Repression; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D009154:Mutation; D015345:Oligonucleotide Probes; D009876:Operon; D010957:Plasmids; D011401:Promoter Regions, Genetic; D015183:Restriction Mapping; D012689:Sequence Homology, Nucleic Acid; D000516:alpha-Amylases / Q000096:biosynthesis / Q000235:genetics*
chemical_list: D004269:DNA, Bacterial; D015345:Oligonucleotide Probes; D000516:alpha-Amylases