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Induction and Elimination of Prophages Using CRISPR Interference.
Jeffrey K Cornuault1,2, Sylvain Moineau1,2,3
1Département de Biochimie, de Mmicrobiologie, et de Bio-informatique, Faculté des sciences et de Génie, Université Laval, Québec City, Canada; Université Laval, Québec City, Canada.
The CRISPR Journal
|August 18, 2021
Summary
CRISPR interference (CRISPRi) effectively induces prophage in bacteria by silencing repressor genes. This method also efficiently cures bacterial strains of unwanted prophages, simplifying research.
Area of Science:
- Bacteriology
- Molecular Biology
- Genetics
Background:
- Prophages are integrated viral DNA within bacterial genomes, influencing host traits.
- Prophage induction, often mediated by the bacterial SOS response, is crucial for phage replication but difficult to control for numerous prophages.
- Current methods for removing prophages from bacterial strains are laborious.
Purpose of the Study:
- To investigate CRISPR interference (CRISPRi) as a novel method for prophage induction.
- To assess the efficacy of CRISPRi in curing lysogenic bacterial strains of prophages.
Main Methods:
- Utilized CRISPR interference (CRISPRi) to transcriptionally silence prophage repressor genes in *Escherichia coli*.
- Employed *E. coli* phages λ and P2 as model systems to validate the CRISPRi approach.
- Evaluated CRISPRi's effectiveness in inducing prophage and eliminating prophages from bacterial hosts.
Main Results:
- Demonstrated that CRISPRi successfully induces prophage in lysogenic *E. coli* strains.
- Showcased CRISPRi's efficiency in curing bacterial strains of prophages λ and P2.
- Confirmed transcriptional silencing of repressor genes leads to prophage induction.
Conclusions:
- CRISPR interference provides a targeted and efficient strategy for prophage induction.
- CRISPRi offers a streamlined approach for curing bacterial strains of inducible prophages.
- This method facilitates the study and manipulation of prophage-host interactions.
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