Fig 2.

(A) A typical “fast-folding” trajectory, which passes through the helix-hairpin 1 (major) intermediate. Folding occurs to less than 1 Å drms. In this particular trajectory, hairpin 2 folds and unfolds independently (labeled by a purple “1” in the Bottom panel), until the helix-hairpin 1 complex folds (“2”) and stabilizes hairpin 2 (“3”). Note that kinetic traps are not encountered. (B) A trajectory monitored by tryptophan burial. The Top panel tracks the burial of tryptophan 43 (W43) relative to the native state for a typical trajectory. Relative burial is computed as follows: (total number of contacts made by W43)/(total number of native contacts made by W43). Significant events encountered in this trajectory are labeled.