Extended Data Fig. 4: Structural details of GI₄-F7.

a, Alignment of the complete cryoEM model to the design model. Major rigid-body DoF deviations are indicated with arrows. Two views of the asu are shown. Approximate locations of each inset (B, C, and D) are indicated. b, Comparison between the cryoEM model (left) and design model (right) of the newly designed nanocage (B-C) interface. Top row, M57 on the CCC-homotrimer changes rotamer to occupy a void in the interface in the design model. Bottom row, F57 on the B chain of the AAB heterotrimer packs against S187 of the CCC homotrimer in the cryoEM model, instead of A190 in the CCC homotrimer as in the design model. c, Comparison of the I3-01 (A-A) interface observed in the cryoEM model to a previously published structure (PDB ID 8ED3; ref. 78). Top row, slight rigid-body deviations from perfect two-fold symmetry in one copy of the A chain. Bottom row, very little deviation from perfect two-fold symmetry. d, Details of the density maps in the regions of the pseudosymmetry-generating mutations within the AAB heterotrimer interface. e, Pseudosymmetric heterotrimer colored by Cα-RMSD to the design model. The positions of the pseudosymmetry-generating mutations are indicated. f, Alignment of the AAB heterotrimer cryoEM model to the design model is viewed from the top, towards the center of the nanocage along the three-fold symmetry axis; g, from the side, tangential to the nanocage surface; and h, from the other side, tangential to the nanocage surface. The position of the A:A and newly designed B:C interfaces are indicated. i, Detail of the B side of the B:C interface, highlighting the most significant deviations from the design model. j, Deviations observed in the cryoEM reconstruction of GI₄-F7 compared to the design model.