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Updated: Jun 20, 2026
06:40
G2-seq: A High Throughput Sequencing-based Technique for Identifying Late Replicating Regions of the Genome
Published on: March 22, 2018
Characterization and comparative sequence analysis of replication origins from three large Bacillus thuringiensis
1Ecogen Inc. Langhorne, Pennsylvania 19047-1810.
Journal of Bacteriology
|September 1, 1991
Summary
Researchers cloned and sequenced three Bacillus thuringiensis plasmid replication origins. These origins are nonhomologous and essential for replication, suggesting independent evolution and distinct protein functions.
Area of Science:
- Microbiology
- Molecular Biology
- Genetics
Background:
- Large plasmids in Bacillus thuringiensis are crucial for genetic traits.
- Understanding plasmid replication mechanisms is key to genetic manipulation.
Purpose of the Study:
- To clone, sequence, and characterize the replication origins of three large Bacillus thuringiensis plasmids.
- To investigate the functional and evolutionary relationships of these replication origins.
Main Methods:
- Cloning of replication origins in Escherichia coli.
- DNA sequencing and sequence analysis.
- Plasmid transformation assays in Bacillus species.
Main Results:
- Three nonhomologous replication origins (ori 43, ori 44, ori 60) were identified and sequenced.
- Each origin contains an essential open reading frame for replication in B. thuringiensis.
- Replication proteins show limited homology to known proteins from other bacteria.
Conclusions:
- The replication origins appear to have independent evolutionary origins.
- The identified replication proteins are essential for plasmid replication in B. thuringiensis.
- These findings contribute to understanding plasmid biology in Bacillus species.
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