Suppression of thermosensitive initiation of DNA replication in a dnaR mutant of Escherichia coli by a rifampin resistance mutation in the rpoB gene.

摘要: The thermosensitivity of the Escherichia coli dnaR130 mutant in initiation DNA replication was suppressed by a spontaneous rifampin resistance mutation rpoB, gene for beta subunit RNA polymerase. Among dnaR-suppressing rpoB alleles obtained rpoB22, which able to suppress dnaA46 or dnaA167 mutant, but not that dnaA5 replication. Some dnaA-suppressing from rifampin-resistant derivatives dnaA mutants were dnaR defect. with rpoB22 allele deprived thermoresistance and viability at low high temperatures mutation. results show rpoB-mediated suppression defect depends on functions both products. I propose product has key role transcriptional activation origin dnaA-dependent