Fig. 5.

Comparison of core packing (a and d positions) for each layer of α₄H, α₄F₃a, and α₄F₃af₃d. The pattern of hydrophobic contacts is generally unchanged by fluorination, despite the hFLeu side chain being significantly larger; exceptions are layer 3 of α₄F₃a, where Leu inserts between hFLeu residues, and layer 1 of α₄F₃af₃d, where fraying of the core results in a cleft opening across the b–e interface.