title: Isolation and expression of a constitutive variant of the chloramphenicol-inducible plasmid gene cat-86 under control of the Bacillus subtilis 168 amylase promoter.
abstract: The amyR1 region controls the regulated expression of the Bacillus subtilis 168 amylase gene amyE. When cloned into the B. subtilis promoter-cloning plasmid pPL603, amyR1 has been shown to activate expression of the promoter-indicator gene cat-86. In this chimeric plasmid, p5' alpha B10, cat-86 expression was maximal in stationary phase B. subtilis cells and cat-86 expression was repressible by glucose. Both these properties are similar to the regulated expression of the B. subtilis amyE gene. In addition, cat-86 expression in p5' alpha B10 was inducible with chloramphenicol (Cm). The inducibility phenotype of cat-86 has been shown to be independent of the promoter that is used to activate the gene, and inducibility has been suggested to result from the presence of a pair of inverted-repeat sequences that span the ribosome-binding site (RBS) for cat-86. A spontaneous deletion mutant of p5' alpha B10 was isolated, p5' alpha B10 delta 1, in which cat-86 expression was constitutive with respect to Cm, but the basic pattern of amyR1-directed regulation of cat-86 was intact. The rightward deletion endpoint was within the upstream member of the pair of inverted repeats that immediately precede cat-86. This result is therefore consistent with the role proposed for the inverted repeats in Cm inducibility. The leftward endpoint of the deletion is within the amyR1 region and thus allows a more precise determination of the functional domain of amyR1.
mesh_terms: D000123:Acetyltransferases / Q000096:biosynthesis / Q000235:genetics*; D001412:Bacillus subtilis / Q000201:enzymology / Q000235:genetics*; D002701:Chloramphenicol / Q000494:pharmacology; D015500:Chloramphenicol O-Acetyltransferase; D002872:Chromosome Deletion; D004269:DNA, Bacterial / Q000235:genetics; D004790:Enzyme Induction / Q000187:drug effects; D005786:Gene Expression Regulation / Q000187:drug effects; D005798:Genes, Bacterial; D014644:Genetic Variation; D009876:Operon; D010957:Plasmids; D000516:alpha-Amylases / Q000235:genetics
chemical_list: D004269:DNA, Bacterial; D002701:Chloramphenicol; D000123:Acetyltransferases; D015500:Chloramphenicol O-Acetyltransferase; D000516:alpha-Amylases