Fig. 4. Moo19 and B2 tail machines.

(Left) Cryo-EM density maps of the C12-symmetrized tail assemblies for Moo19 and B2. (Right) Atomic models built from the EM density map. The portal shown in red was modeled from residues 17 to 675 of 760 total for Moo19 and residues 182 to 679 of 706 total for B2. The N-terminal portions of tailspike shown in yellow (residues 10 to 74 per monomer in each trimer) were also modeled. The adaptor proteins were largely complete with all 234 residues modeled for Moo19 and residues 2 to 233 of 234 total for B2. Last, the tail tube shown in blue was modeled for residues 4 to 278 of 279 for Moo19 and residues 3 to 200 of 206 for B2.