13C APSY-NMR for sequential assignment of intrinsically disordered proteins.

The increasingly recognized biological relevance of intrinsically disordered proteins requires a continuous expansion of the tools for their characterization via NMR spectroscopy, the only technique so far able to provide atomic-resolution information on these highly mobile macromolecules. Here we present the implementation of projection spectroscopy in 13C-direct detected NMR experiments to achieve the sequence specific assignment of IDPs. The approach was used to obtain the complete backbone assignment at high temperature of α-synuclein, a paradigmatic intrinsically disordered protein.