Fig. 2

Molecular models of the SAPN-P27-2 (top) and SAPN-Combo (bottom) assuming icosahedral symmetry. The view is down the fivefold symmetry axis. a, c Molecular models of the monomers; b, d molecular models of the particle. The color coding of the models is indicated in the sequences of the protein chains below. Monomers and particles are both drawn to size between SAPN-P27-2 and SAPN-Combo. The epitope P27-C is clearly more exposed within the particle than the epitope P27-N, i.e. access to P27-N is more restricted