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Updated: Jul 28, 2026
11:19
Inducing a Site Specific Replication Blockage in E. coli Using a Fluorescent Repressor Operator System
Published on: August 21, 2016
Cellular localisation of the clamp protein during DNA replication
Kritaya Kongsuwan1, Brian P Dalrymple, Gene Wijffels
1CSIRO Division of Livestock Industries, 120 Meiers Road, 4068, Indooroopilly, Qld, Australia. kritaya.kongsuwan@csiro.au
FEMS Microbiology Letters
|November 19, 2002
Summary
Green fluorescent protein (GFP) fused to the beta subunit of DNA polymerase III visualized bacterial DNA replication. This fusion protein
Area of Science:
- Microbiology
- Molecular Biology
- Biochemistry
Background:
- Escherichia coli DNA polymerase III holoenzyme is crucial for DNA replication.
- Visualizing protein dynamics during bacterial DNA replication is essential for understanding cell division.
Purpose of the Study:
- To visualize the dynamics of the beta subunit of DNA polymerase III during DNA replication in live Escherichia coli cells.
- To investigate the spatiotemporal localization of DNA polymerase III during replication.
Main Methods:
- Gene fusion of beta subunit with green fluorescent protein (GFP).
- Expression of the GFP-beta fusion protein in Escherichia coli under lac promoter control.
- Microscopy to observe fluorescent foci in live cells.
Main Results:
- Formation of GFP-beta fluorescent foci required DNA replication.
- The number of GFP-beta foci per cell correlated with cell growth rate.
- GFP-beta foci localized near the midcell and migrated to opposite poles during replication.
Conclusions:
- The GFP-beta fusion protein serves as a reliable marker for DNA replication in Escherichia coli.
- The observed dynamics of GFP-beta foci suggest a coordinated process of DNA replication and segregation.
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