Abolishing "structural blindness" in metalloproteins: PioC, a NOE-less protein structure

Almost half of all known enzymes are metalloproteins where themetal center(s) are essential for catalysis, electron transfer, metalstorage/transport, or provide stability and structural properties.NMR is a privileged method for characterizing metalloproteinsproviding the structure at atomic resolution, information aboutamplitude and time-scale of internal dynamics, hints on elec-tronic structure and oxidation states in conditions that mimic thephysiological context. However, in a significant part of the metal-loproteome the metal ion is paramagnetic and, in its vicinity, a“blind sphere” exists where nuclear relaxation is enhanced andsignal detection becomes a challenge