For this new study, we added a suite of additional assemblies with different oligomerization states. Modification of the a and d positions in the heptad can be exploited to alter coiled-coil assembly state (Fig. ). For instance substitution of a and d positions to either all isoleucine or alternating leucine and isoleucine residues were designed to produce parallel coiled-coil homotrimer CC-Tri_E1 and homotetramer CC-Tet_E1, respectively (Table ). We selected the E1 rather than E2 graft for this series as a balance between MCL-1 binding potency and coiled-coil stability. These peptides were anticipated to present three or four copies of the E1 motif on their outer surfaces, respectively. As a control, an analogous partly helical but monomeric peptide (Mono_E1) was generated by substituting the a and d positions to alanine, which should not form a stable coiled-coil assembly, but still presents the identified E1 binding motif.