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Updated: May 12, 2026

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Tools to Study the Role of Architectural Protein HMGB1 in the Processing of Helix Distorting, Site-specific DNA Interstrand Crosslinks
Published on: November 10, 2016
Host protein requirements for in vitro site-specific DNA inversion
Cell
|August 15, 1986
Summary
Flagellar phase variation involves DNA inversion, significantly enhanced by a specific sequence. Purified proteins, including Hin recombinase and host factors, mediate this process, with HU protein
Area of Science:
- Molecular Biology
- Genetics
- Microbiology
Background:
- Flagellar phase variation is a mechanism for bacterial immune evasion.
- This variation is controlled by DNA inversion at specific recombination sites.
Purpose of the Study:
- To investigate the molecular mechanisms of flagellar phase variation.
- To identify and characterize the protein factors involved in DNA inversion.
Main Methods:
- Purification of protein components required for DNA inversion.
- Analysis of the role of a recombinational enhancer sequence.
- Investigating the dependence of recombination rate on specific proteins.
Main Results:
- A 60 bp recombinational enhancer sequence stimulated inversion rate 150-fold.
- Key proteins identified: Hin recombinase, Factor II, and E. coli HU.
- Recombination rate dependence on HU varied with enhancer location.
Conclusions:
- The recombinational enhancer significantly boosts DNA inversion efficiency.
- Hin, Factor II, and HU are crucial for site-specific recombination in flagellar phase variation.
- The interplay between HU, Factor II, and the enhancer is vital for regulating this genetic process.
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