Proteomic methods for the identification of intrinsically disordered proteins.

Intrinsically disordered proteins (IDPs) lack fixed 3D structure under physiological conditions, yet they often carry out critically important physiological functions. The first few disordered proteins have been discovered one-by-one from clues that suggested that a protein lacks structure. Since bioinformatic predictions suggest that a large portion of eukaryotic proteomes contains significant levels of protein disorder, a reliable method for the large-scale separation and identification of these proteins is needed. IDPs do not undergo large-scale structural changes and aggregation at low pH or elevated temperatures. Thus, such proteins are likely to remain soluble under these extreme conditions, making acid treatment and/or heat treatment suitable for substantial enrichment of intrinsically unfolded proteins in the soluble fraction.