title: Temperature-sensitive catabolite activator protein in Escherichia coli BUG6.
abstract: BUG6 is a temperature-sensitive cell division mutant which forms filaments at the nonpermissive temperature. Synthesis of the maltose- and galactose-binding protein-dependent transport systems is also temperature sensitive in BUG6. Using operon and protein fusions of the maltose transport genes to lacZ, we observed that the temperature-sensitive control of the maltose transport system in BUG6 occurs at the transcriptional level. By P1-mediated transductions, we found that BUG6 contains two independent temperature-sensitive mutations. One maps between 2 and 3 min on the Escherichia coli linkage map, in close proximity to the fts-envA region. This mutation is responsible for temperature-sensitive cell division. The other mutation maps at 73 min in crp, the structural gene of the catabolite activator protein. The latter could be complemented by a hybrid plasmid carrying the wild-type crp as the only gene on a 0.9-kilobase HindIII-AluI restriction fragment. The mutation in crp alone was found to be responsible for the temperature-sensitive synthesis of the maltose transport system. Although it causes a complete block of transcription of the maltose transport genes at 41 degrees C, this mutation had only a marginal effect on the transcription of the lac operon.
authors.forename: D
authors.initials: D
authors.lastname: Benner
authors.forename: N
authors.initials: N
authors.lastname: Müller
authors.forename: W
authors.initials: W
authors.lastname: Boos
mesh_terms: D018528:ATP-Binding Cassette Transporters; D010582:Bacteriophage lambda / Q000235:genetics; D002352:Carrier Proteins / Q000235:genetics; D002455:Cell Division; D004926:Escherichia coli / Q000235:genetics*; D029968:Escherichia coli Proteins; D007763:Lac Operon; D058619:Maltose-Binding Proteins; D009004:Monosaccharide Transport Proteins; D009154:Mutation; D011953:Receptors, Cyclic AMP / Q000235:genetics*; D013696:Temperature; D014158:Transcription, Genetic; D014161:Transduction, Genetic; D014169:Transformation, Bacterial
chemical_list: D018528:ATP-Binding Cassette Transporters; D002352:Carrier Proteins; D029968:Escherichia coli Proteins; D058619:Maltose-Binding Proteins; D009004:Monosaccharide Transport Proteins; D011953:Receptors, Cyclic AMP; C461599:maltose transport system, E coli