Figure 4.

(A) Hydrophobic core formation during HP35 folding (the D state has a fully disordered tertiary structure; in the I state, the first and second helices formed but it still has an incomplete hydrophobic core; the N state has a tightly packed hydrophobic core). (B) A native-like structure with an incompletely folded hydrophobic core from the intermediate state (single snapshot). (C) Contact formation between side-chains Trp64 and Phe76 (the I state has contact between Trp64 and Phe76; the TS2 state shows the absence of Trp-Phe contact). The average configurations are taken from Figure 1.