2003/08/22 by Morigen Morigen, Anders Løbner‐Olesen, Kirsten Skarstad · 1 citation
Biochemistry, Genetics and Molecular Biology · #DNA Repair Mechanisms #Bacterial Genetics and Biotechnology #DNA and Nucleic Acid Chemistry
paper · pdf · doi:10.1046/j.1365-2958.2003.03695.x
openalex publication_date 2003/08/22 · openalex created_date 2016/06/24 · openalex updated_date 2026/06/22
In Escherichia coli, the level of the initiator protein DnaA is limiting for initiation of replication at oriC. A high-affinity binding site for DnaA, datA, plays an important role. Here, the effect of extra datA sites was studied. A moderate increase in datA dosage ( approximately fourfold) delayed initiation of replication and cell division, but increased the rate of replication fork movement about twofold. At a further increase in the datA gene dosage, the SOS response was induced, and incomplete rounds of chromosome replication were detected. Overexpression of DnaA protein suppressed the SOS response and restored normal replication timing and rate of fork movement. In the presence of extra datA sites, cells showed a dependency on PriA and RecA proteins, indicating instability of the replication fork. The results suggest that wild-type replication fork progression normally includes controlled pausing, and that this is a prerequisite for normal replication fork function.