Fig. 3.

Characterization of long-armed junctions by negative stain EM. The designs shown match the EM averages at the resolution of the technique. Column 1: design model with each junction in a different shade of green or blue. Column 2: negative stain micrographs. Column 3: 2D class averages of the designs; the different views and orientations are consistent with the design models. A and B are symmetric oligomers composed of a homotrimer (9) and a repeat protein connected via a junction. C and D are monomeric designs composed of two repeat proteins connected by one junction, or three repeat protein connected by two junctions, respectively.