Competing Ligands Can Both Obstruct and Enhance Protein-Complex Formation (Biophysical Journal)

Specific molecular recognition is a basic requirement for life. In physical terms, the source of interaction specificity that favors a small set of specific interactions over the multitude of possibilities is evolutionary favored, but how this drives evolution is still an open question (1-3). Although nonspecific interactions are typically weak and short-lived, they are still expected to affect function because of their sheer numbers in the crowded milieu of the cell. Both specific and nonspecific interactions form weak encounters with other proteins.