Folding in a crowd

Interactions between a protein and large nearby molecules produce repulsive forces at distances that can be as large as the protein itself. The group modeled the energetic effects of these interactions on folding of a WW domain and found that it folds faster and has a more stable folded state in a crowded environment. The more spread out the protein, the more likely it is to experience unfavorable interactions with macromolecules. Compaction, in contrast, promotes its isolation.

Folding rates reach a maximum when 10% of the solution volume is taken up by other large molecules, but even at high densities the folding rates were still well above that...