Chassis

In our project, we used E.coli BW25113 strain with OmpA gene knocked out for the reason that the absence of OmpA protein would lead to hyper-vesiculation, meaning increased production of outer membrane vesicles (OMVs).

Inside the periplasm there is a thin, rigid peptidoglycan(PG) layer attached to both outer membrane and cytoplasmic membrane by membrane anchored proteins.[Fig. 1](1) Deletion or truncation of OmpA, an abundant protein linking the outer membrane and peptidoglycan layer, will therefore result in increased vesiculation in E. coli, Salmonella, and Vibrio cholerae (2) as the Figure 1 lack of OmpA destabilises the periplasm’s structure.This will result in greater likelihood that our Cas9 protein will be encapsulated into OMVs.