title: The effect of spo0 mutations on the expression of spo0A- and spo0F-lacZ fusions.
abstract: We have constructed spo0A-lacZ and spo0F-lacZ fusions with a temperate phage vector and have investigated how spo0 gene products are involved in the expression of each of these genes. The expression of spo0A-lacZ and spo0F-lacZ was stimulated at about the time of cessation of vegetative growth in Spo+ cells. This stimulation of spo0A-lacZ was impaired by mutations in the spo0B, D, E, F or H genes but was not affected by mutations in the spo0J or K genes. Similar results were obtained with the spo0F-lacZ fusion. The effect of the spo0A mutation on spo0A-lacZ expression was characteristic: the spo0A-directed beta-galactosidase activity found during vegetative growth was significantly enhanced in the spo0A mutant. This result suggests that spo0A gene expression is auto-regulated being repressed by its own gene product. Another remarkable observation was the effect of the sof-1 mutation, which is known to be a spo0A allele; it suppressed the sporulation deficiency of spo0B, spo0D and spo0F mutants. The spo0A-lacZ stimulation, which is impaired by any one of these spo0 mutations, was restored by the additional sof-1 mutation.
mesh_terms: D001412:Bacillus subtilis / Q000235:genetics*; D003090:Coliphages / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics*; D005796:Genes; D005798:Genes, Bacterial; D005838:Genotype; D007763:Lac Operon; D009154:Mutation; D010957:Plasmids; D013171:Spores, Bacterial / Q000502:physiology; D001616:beta-Galactosidase / Q000235:genetics
chemical_list: D001616:beta-Galactosidase