Figure 5:

ICP0 tetramer assembly with subunits colored A (magenta), B (tan), C (cyan) and D (green). A) View along the crystallographic 2-fold axis. The dashed arrows indicate the direction of the β-barrel-like motifs as viewed in Figure 4B. B) View perpendicular to the crystallographic 2-fold axis. The β6 and β7 strands which form hydrogen bond interactions are indicated. C) The regions in circles are the extended β-barrel-like motifs viewed along the barrel axis. D) Electrostatic surface of the ICP0 tetramer with the residues contributing to the positive/negative patches indicated. The scale is from −0.5 V (red) to 0.5 V (blue).