FIGURE 5.

Phage EfV12-phi1 evolved tandem duplications in the tail fiber gene to increase its infectivity. (A) Average coverage along the phage genome for the phage population of replicate 2 at the final timepoint. Duplication was first noticed by this spike in sequencing coverage. Reads were mapped to the original phage genome so the duplication in the tail fiber appears as a spike in coverage. (B) Duplications in the tail fiber visualized by PCR using primers that flank the tail fiber. Duplications resulted in a larger amplicon. Each replicate population at the final timepoint is shown as well as the ancestral phage. (C) Presence of tail fiber duplications over time shown by the fold coverage increase in the duplicated region divided by the average coverage of the rest of the phage genome. (D) Schematic of the phage tail fiber tandem duplication within the gene. Reads spanning the tail fiber gene containing up to three duplications (four total copies of duplicated sequence) were seen with MinION long read sequencing.