ADAM8 and infection: At least one crRNA targeting each of the four known MS2 genes inhibited infection, while crRNAs targeting inside the coding sequence (CDS) but outside of the susceptible RBS region (Fig. 1d and Supplementary Fig. 1b) on either +sense or −sense RNA strands did not, ruling out direct obstruction of genome synthesis (Fig. 3d and Supplementary Fig. 11a,b).