CP and infection: Similarly, the CP8unalikevirus phage CP_F1 showed decreased infection efficiency on non-motile cells, as infection of flaA and flaAB mutant strains yielded reduced efficiency of plating (EOP) values (flaA 0.08 ± 0.04, n = 3; flaAB 0.12 ± 0.03, n = 3) and highly opaque plaques.