Fig. 4: Structure of the tail terminator gp15 hexamer and its interactions with gp18 sheath.

The gp15 chains are rainbow colored from the N-terminus (blue) to the C-terminus (red). The gp3 protein is shown in magenta, and gp18 is shown in green. a Side view showing the gp15 hexamer sitting at the top of the tail. b Side view of the gp15 hexamer. c Top view of the gp15 hexamer. d One gp15 subunit. e Gp15 subunit interacting with the gp18 subunit from the top ring of the sheath.