Type IV-A and Type I-Fv application to genome reduction

A fusion of the HNH domain of CasDinG from Sulfitobacter sp. JL08 (SsCasDinG) to the characterized type IV-A1 CasDinG of Pseudomonas oleovorans (PoCasDinG) was created. An engineered catalytic active type IV-A1 CRISPR-Cas system able to processive degrade target DNA in vivo. Using whole genome sequencing we analyzed the effects on the genome reduction in E. coli BL21-AI also in comparison to the type I-Fv system of Shewanella putrefaciens in association with its CasDinG. This study provides the basis to use the type I-Fv and the engineered type IV-A1 systems as tools in genome reduction and helps to understand the DNA repair mechanisms used to fix CRISPR-Cas induced lesions.