Fig. 2:

Diverse pac site phage TerS structures from electron micrographs and crystallography. Pac site phage identities P22, SF6, and 44RR are given in the figure and the crystal structures are referenced in the text. The location of the phage T4 TerS gp16 ts mutation Q59Y used for temperature regulated renaturation determined by FRET (shown in Fig. 6) is displayed in the 44RR crystal structure (Sun et al., 2012). The top half electron micrograph figure and mass determination of T4 TerS protein only single and dimeric rings is from reference (Lin et al., 1997), as confirmed and refined by (van Duijn, 2010), the bottom half figure is from the protein data bank (PDB).