Probing the interaction of lipids with the non-annular binding sites of the potassium channel KcsA by magic-angle spinning NMR

► Solid-state 31P MAS NMR studies have been used to characterise binding to the non-annular binding site of KcsA. ► Residues R64 and R89 have been identified as important in the recognition of anionic lipids in the non-annular binding site. ► Single-channel current recordings demonstrate the functional importance of these interactions for KcsA activity.