Defining conformational ensembles of intrinsically disordered and partially folded proteins directly from chemical shifts.

The development of meaningful descriptions of the conformational behavior of intrinsically disordered proteins represents a key challenge for contemporary structural biology. An approach is developed, based on the combination of ensemble descriptions of unfolded proteins and state-of-the-art chemical shift prediction algorithms, to describe backbone dihedral angle conformational behavior on the basis of (13)C and (15)N NMR chemical shifts alone. This allows the identification and characterization of entire secondary structural elements and their associated populations, as well as providing indications of the subtle detail of local conformational sampling in unfolded proteins.