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Updated: May 15, 2026
11:12
Determination of the Optimal Chromosomal Location(s) for a DNA Element in Escherichia coli Using a Novel Transposon-mediated Approach
Published on: September 11, 2017
DnaA binding locus datA promotes DnaA-ATP hydrolysis to enable cell cycle-coordinated replication initiation
Kazutoshi Kasho1, Tsutomu Katayama
1Department of Molecular Biology, Graduate School of Pharmaceutical Sciences, Kyushu University, Fukuoka 812-8582, Japan.
Summary
A new system involving the datA site and integration host factor (IHF) aids in inactivating ATP-DnaA, complementing the known RIDA pathway for DNA replication control in E. coli.
Area of Science:
- Microbiology
- Molecular Biology
- Genetics
Background:
- Cell cycle regulation ensures DNA replication occurs precisely once per cell cycle.
- In Escherichia coli, ATP-DnaA is the key initiator, and its activity is tightly controlled.
- Regulatory Inactivation of DnaA (RIDA) is a known mechanism for DnaA-ATP hydrolysis.
Purpose of the Study:
- To investigate a potential second system for DnaA-ATP hydrolysis at the datA locus.
- To understand the role of integration host factor (IHF) in regulating DnaA activity at datA.
- To elucidate the interplay between RIDA and the datA-IHF system in cell cycle control.
Main Methods:
- Investigated DnaA-ATP hydrolysis at the datA locus.
- Utilized deletion mutants for datA and ihf genes.
- Performed cell-cycle analysis to determine the timing of IHF binding to datA.
Main Results:
- A datA-IHF complex promotes DnaA-ATP hydrolysis, dependent on inter-DnaA interactions.
- Deletion of datA or ihf elevates ATP-DnaA levels, particularly in RIDA-defective cells.
- IHF binds to datA post-replication initiation, coinciding with RIDA activation.
Conclusions:
- A second DnaA-ATP hydrolysis system involving datA and IHF exists in E. coli.
- This datA-IHF system works in concert with RIDA to regulate ATP-DnaA levels.
- This coordinated regulation ensures precise cell cycle-dependent initiation of DNA replication.
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