Fig. 4

Optimization of the two-step RAPID CRISPR–Cpf1 system. a Different operating procedures for the RAPID system, scheme 1—the transformants are cultured in liquid medium without IPTG induction after 2 h recovery, prior to inoculation onto solid medium supplemented with IPTG. scheme 2—is the same as scheme 1, except that IPTG is added to the liquid culture. scheme 3—the transformants are recovered for a different time duration and directly spread onto a solid medium supplemented with IPTG. b Gene deletion efficiencies for different operating schemes. c Promoter optimization for RecET expression. d Integration efficiencies for fragments of different sizes. e Gene deletion and integration efficiencies using linear DNA template. Experiments were performed in triplicates. Values are presented as mean ± SD. *P < 0.05, **P < 0.01, *** P < 0.001; n.s., not significant