Fig. S6.

Snapshot from MD simulations illustrating the interaction between C-terminal residues of two R10 molecules at close separation. Dashed lines represent the hydrogen bonds between the negatively charged carboxyl groups and the positively charged guanidinium moieties of the ninth residues. Colored circles represent the probability of H bonds between the carboxyl groups of one peptide and the last five residues of the other peptide. Probabilities are obtained from MD simulations performed using the A99 force field and constraining the separations between the ninth residues’ guanidino-C atoms to 0.42 $\pm$ 0.04 nm.