Summary
Smooth protein folding landscapes are the result of natural selection (1). This was the conclusion after observing that the de novo designed protein Top7 has a multiphasic folding pathway.
See also
1.
Watters AL, Deka P, Corrent C, Callender D, Varani G, Sosnick T, et al. The Highly Cooperative Folding of Small Naturally Occurring Proteins Is Likely the Result of Natural Selection. Cell. 2007;128(3):613–24. Available from: https://doi.org/10.1016/j.cell.2006.12.042