Regulation of chromosomal replication in E. coli: sequestration and beyond
Article Abstract:
The timing of the replication of the Escherichia coli chromosome depends on methylated form of oriC, SeqA protein, DnaA protein and acidic phospholipids. Methylated oriC stimulates transcription while the SeqA protein inhibits transcription. Inhibition of replication is either due to the binding of SeqA to oriC to stop the formation of an open complex or by controlling the activity of the DnaA protein, an inhibiting factor. The acidic phospholipids and oriC converts the inactive ADP-DnaA form into the active ATP-bound form. Sequestering prevents replication in recently formed fragments.
Publication Name: Cell
Subject: Biological sciences
ISSN: 0092-8674
Year: 1995
User Contributions:
Comment about this article or add new information about this topic:
The initiator function of DnaA protein is negatively regulated by the sliding clamp of the E. coli chromosomal replicase
Article Abstract:
The beta subunit of DNA polymerase III in Escherichia coli is essential for negative regulation of the initiator protein, DnaA. This ability to inactivate DnaA depends on the beta subunit's assembly as a sliding clamp on DNA and a partially purified factor IdaB protein. The DnaA inactivation is further stimulated by DNA synthesis, suggesting a close linkage between initiator inactivation and replication. In vivo, DnaA takes on the ADP form. This supports the hypothesis that the initiator is negatively regulated by action of the replicase.
Publication Name: Cell
Subject: Biological sciences
ISSN: 0092-8674
Year: 1998
User Contributions:
Comment about this article or add new information about this topic:
E. coli SeqA protein binds oriC in two different methyl-modulated reactions appropriate to its roles in DNA replication initiation and origin sequestration
Article Abstract:
The seqA gene of Escherichia coli controls both the initiation of replication and sequestration in the chromosome by direct interaction with the replication origin oriC. The binding of the protein SeqA to methylated oriC and hemimethylated DNA is strong and specific. SeqA also controls the binding of hemimethylated oriC to other membrane fragments. The initiation of replication is by methylation of oriC and sequestration takes place in the methylated structures formed by replication.
Publication Name: Cell
Subject: Biological sciences
ISSN: 0092-8674
Year: 1995
User Contributions:
Comment about this article or add new information about this topic:
- Abstracts: Cell elongation is key to in silico replication of in vitro vasculogenesis and subsequent remodeling. Spatiotemporal characterization of short versus long duration calcium transients in embryonic muscle and their role in myofibrillogenesis
- Abstracts: Classification of human chromosome 21 gene-expression variations in Down syndrome: impact on disease phenotypes
- Abstracts: Relatedness of penicillin-resistant Streptococcus pneumoniae serogroup 9 strains from France and Spain. Electrotransformation of Streptococcus pneumoniae: evidence for restriction of DNA on entry
- Abstracts: Timing and genetic regulation of commitment to sporulation in Bacillus subtilis. Medium-dependent sporulation resulting from a mutation in the spollAB gene of Bacillus subtilis
- Abstracts: Uptake and retention of Vibrio cholerae O1 in the Eastern oyster, Crassostrea virginica. Pulsed-field gel electrophoresis and ribotype profiles of clinical and environmental Vibrio vulnificus isolates