Structure of DPS determined at 100 keV. (a) Typical micrograph of DPS after motion correction. Contrast is adjusted to ±3σ from the mean intensity. (b) 2D class averages. (c) Sharpened masked 3D reconstruction of DPS from N = 16 507 particles with tetrahedral (T) symmetry. (d) Gold-standard FSC plot corresponding to the calculated map, showing the correlation between the phase-randomized (yellow), unmasked (blue) and masked (red) half-maps. The plot terminates at the Nyquist frequency. (e) Orientation distribution of the DPS particles contributing to the final reconstruction (Mollweide projection). All Euler angles are assigned within one asymmetric subunit for the tetrahedrally (T) symmetric particle. The colour scale (linear) corresponds to the normalized density of views (blue, low; red, high). E = 0.9 is the efficiency of the orientation distribution, indicating nearly uniform sampling of the particle views.