Figure 6.

Global analysis of BH3-derived α/β-peptide binding to Bcl-x_L (upper panel) or Mcl-1 (lower panel). The numbers across the top of each panel correspond to the sequence positions in the Bim-derived 18-mers introduced in this paper (Figure 1). Five positions characteristic of BH3 domains, four hydrophobic residues (h1–h4) and an Asp residue (D) are indicated. The leftmost column of each panel classifies the α/β-peptides as strong or weak binders to the relevant pro-survival protein. The next column identifies each α- or α/β-peptide, with number designations as in Figure 1. The remaining columns indicate whether the indicated position within the designated α/β-peptide is occupied by a β³-residue (blue box) or by an α-residue (white or green box). The green boxes highlight positions in strong binders that appear to require an α-residue to form a complex with Bcl-x_L (upper panel) or with Mcl-1 (lower panel).