Identification of intrinsic disorder in complexes from Protein Data Bank

Intrinsically disordered proteins or regions (IDPs or IDRs) lack stable structures in solution yet often fold upon binding with partners. IDPs or IDRs are highly abundant in all proteomes and represent a significant modification of the sequence → structure → function paradigm. In this study, we first present the results of various disorder predictions on a non-redundant set of PDB complexes. Further, structural formation by these predicted-to-be-disordered proteins was observed to depend upon various factors (including hetero group binding, protein/DNA/RNA binding, disulfide bonds, and ion binding). This study provides additional support for the newly proposed paradigm of sequence → IDP/IDR ensemble → function.