Efficient Genome Engineering of a Virulent Klebsiella Bacteriophage Using CRISPR-Cas9

In the present study, we have addressed efficient, time-saving, and cost-effective CRISPR-based phage genome editing ofKlebsiella phage, which has the potential to significantly expand our knowledge of phage-host interactions and to promote applications of phage therapy. The distribution of sgRNA activity was first evaluated in phages. Short homologous arms were proven to be enough to introduce point mutation, small frameshift deletion, gene deletion, and swap into phages, and weak sgRNAs were proven useful for precise phage genome editing but failed to select random recombinants, all of which makes the CRISPR-based phage genome-editing method easier to use.