Insertion sequence-excision enhancer removes transposable elements from bacterial genomes and induces various genomic
Masahiro Kusumoto1, Tadasuke Ooka, Yoshiaki Nishiya
1Safety Research Team, National Institute of Animal Health, 3-1-5 Kannondai, Tsukuba, Ibaraki 305-0856, Japan.
Nature Communications
|January 13, 2011
Summary
A novel protein, IS-excision enhancer (IEE), promotes the frequent removal of insertion sequences (ISs) from bacterial genomes. This discovery challenges previous notions and highlights IEE
Area of Science:
- Bacterial genetics
- Molecular biology
- Genomics
Background:
- Insertion sequences (ISs) are bacterial mobile genetic elements.
- IS excision was thought to be rare due to lack of bacterial DNA repair mechanisms.
Purpose of the Study:
- To identify mechanisms promoting IS excision in bacteria.
- To characterize a novel protein involved in IS removal.
Main Methods:
- Investigated IS629 excision in Escherichia coli O157.
- Identified and characterized the IS-excision enhancer (IEE) protein.
- Analyzed genomic deletions resulting from IEE-mediated IS excision.
Main Results:
- Discovered IS-excision enhancer (IEE) protein that facilitates frequent IS629 excision.
- IEE acts in a transposase-dependent manner.
- IEE promotes excision of various IS elements and induces genomic deletions.
- IEE homologues are widespread in bacteria, suggesting coevolution with IS elements.
Conclusions:
- IEE is a key factor in bacterial IS element dynamics.
- IEE plays a significant role in bacterial genome evolution through IS removal and deletion.
- IEE represents a novel target for understanding and potentially manipulating bacterial genome plasticity.
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