An adapted method for Cas9-mediated editing reveals the species-specific role of β-glucoside utilization driving competition between Klebsiella species.

. We then adapted a recently developed protocol for functional complementation based on universal "bookmark" targets applicable to all tested species. In summary, species-specific adaptation of state-of-the-art genetic tools allows efficient gene deletion and complementation in type strains as well as natural isolates of KoSC members to study microbial interactions.