Suppression of initiation defects of chromosome replication in Bacillus subtilis dnaA and oriC-deleted mutants by integration of a plasmid replicon into the chromosomes.

摘要: We constructed Bacillus subtilis strains in which chromosome replication initiates from the minimal replicon of a plasmid isolated natto, independently oriC. Integration either orientation at proA locus (115 degrees on genetic map) suppressed temperature-sensitive phenotype caused by mutation dnaA, gene required for initiation In addition, strain with integrated into chromosome, we were able to delete sequences oriC function. These viable but had slower growth rate than oriC+ strains. Marker frequency analysis revealed that both pyrD and metD, genes close proA, showed highest values among markers (genes) measured, those other decreased symmetrically distance site integration (proA). results indicated operated as new sole origin these mode was bidirectional. Interestingly, mutants produced anucleate cells high (about 40% exponential culture), distribution chromosomes irregular. A change mechanism (from system) appears have resulted drastic alteration coordination between partition or cell division.