Folding of A Three-Helix Bundle at the Folding Speed Limit

Abstract

We show in this Letter that a double mutant (K5I/K39V) of 1prb7-53, the GA module of an albumin binding domain, has a maximum folding rate constant of ∼1 (μs)-1. This value is comparable to the estimated theoretical speed limit for protein folding. In addition, we found that the mean hydrophobicity of a given tertiary fold plays an important role in controlling its folding rate.