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Scientists have discovered a bacteriophage that can evade CRISPR-Cas nuclease.


Scientists have discovered a bacteriophage that can evade the CRISPR-Cas system of bacteria. The bacteriophage protects its own DNA by forming a nucleus-like compartment and thus shields its own DNA from the CRISPR nuclease.

Bacteria have a various defense system that protects them from Bacteriophages. The most important system was Restriction modification (RM) system and CRISPR Cas system. Virus must evolve to avoid these immune pathways of bacteria that targets nucleic acids. The researchers found that jumbo phages (ФKZ) that target pseudomonas were resistant to CRISPR Cas9. On further investigation, they observed a proteinaceous nucleus-like compartment in which the replication of phages DNA takes place. Proteins that are involve in replication, transcription and recombination are localized within the compartment. The compartment blocks that CRISPR nuclease form targeting DNA. This study was published in the journal Nature.


References: A bacteriophages nucleus-like compartment shields DNA from CRISPR nuclease. Nature (2019)
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