Movie S1.

A movie showing one of the folding trajectories. The simulation starts in the unfolded state and reaches the native state in which all three disulfide bonds are formed. The movie vividly illustrates that the polypeptide undergoes collapse, resulting in the β-sheet formation. Subsequently, [14–38] forms rearranging to other two native disulfide bonds. In all of the rearrangements, there is considerable expansion in the chain.