Atomic-resolution structures of capsids are available for PC2, STNV, STMV, SPMV, PaV, BMV, and CCMV (Jones and Liljas, 1984; Ban and McPherson, 1995; Speir et al., 1995; Larson et al., 1998; Tang et al., 2001; Lucas et al., 2002; Khayat et al., 2011). For each capsid structure, we estimated the radius by fitting the radial density of capsid protein (C, N, S, O atoms), as plotted here, to a Gaussian. For capsids, we scaled the inradius of our dodecahedral model capsid (Figure 1) until its interior volume was equal to the volume of a sphere with the radius of the biological capsid. The ARMs were anchored as shown in Figure 1, midway across the pentagonal radius (we found that changing the locations of anchor points did not substantially affect ), and the sequence of positive, negative, and neutral beads was set to match the amino acid sequence of the capsid protein for the virus being modeled. For capsids, an icosahedrally symmetric capsid was designed with the excluders and ARMs placed based on the crystal structure of the Brome Mosaic Virus (Lucas et al., 2002). For other viruses the ARM sequence and capsid radius were adjusted. For the satellite viruses, there are basic residues located on the capsid inner surface (in addition to those found in the ARM); for each such residue a positive charge was rigidly fixed to the inner surface of the model capsid. No atomic-resolution structures for capsids of viruses in the Nanoviridae family are available, so the capsid radius for BBT was based on electron microscopy (Harding et al., 1991).