In (a) and (b) are van der Waals surface representations of the PMV virion viewed along icosahedral threefold and fivefold axes, respectively. The quasi hexamer of three B and three C subunits of PMV with neighboring subunits, as they are organized about a true threefold axis, is shown in (c), and the pentamer of A subunits with neighbors in (d). The A subunits are in blue, the B subunits in yellow, and the C subunits in pink. In (e) and (f) are the electrostatic potential distributions of the exterior and interior surfaces, respectively, of a PMV pentamer. The kT/e level is 4.7 for both images.