Related Experiment Videos
Site-specific recombination of bacteriophage P22 does not require integration host factor
1Department of Science Education, Kwangju 501-759, Korea, and Department of Microbiology, University of Illinois, Urbana, Illinois 61801, USA. ehcho@chosum.ac.kr
Journal of Bacteriology
|July 10, 1999
Summary
Bacteriophage P22 site-specific recombination occurs efficiently without Integration Host Factor (IHF), unlike phage lambda. This suggests alternative mechanisms or factors can facilitate P22 recombination complex formation.
Area of Science:
- Molecular Biology
- Virology
- Genetics
Background:
- Site-specific recombination is crucial for viral integration into host genomes.
- Phage lambda utilizes Integration Host Factor (IHF) to bend DNA, facilitating recombination complex formation.
- IHF is essential for efficient lambda recombination, with mutants showing over 1,000-fold reduction.
Purpose of the Study:
- To investigate the role of Integration Host Factor (IHF) in the site-specific recombination of bacteriophage P22.
- To compare the IHF dependency of P22 recombination with that of phage lambda.
Main Methods:
- In vivo measurements of P22 phage integration and excision frequencies.
- Plasmid integration assays in wild-type and ihfA mutant Escherichia coli cells.
- Assessing P22 recombination efficiency in E. coli lacking functional IHF.
Main Results:
- Bacteriophage P22 achieved maximum site-specific recombination efficiency in vivo, even in the absence of IHF.
- Plasmid integration assays demonstrated equal efficiency in wild-type and ihfA mutant cells.
- P22 integrative recombination remained efficient in Escherichia coli lacking functional IHF.
Conclusions:
- Site-specific recombination by bacteriophage P22 does not strictly require Integration Host Factor (IHF).
- Nucleoprotein complexes for P22 recombination can form efficiently without IHF.
- Alternative factors may substitute for IHF in facilitating P22 recombination complex formation.