title: Gramicidin A crystals contain two cation binding sites per channel.
mesh_terms: D001665:Binding Sites; D002586:Cesium; D003461:Crystallography; D004553:Electric Conductivity; D005583:Fourier Analysis; D006096:Gramicidin; D007473:Ion Channels / Q000648:ultrastructure*; D008968:Molecular Conformation; D011188:Potassium
chemical_list: D007473:Ion Channels; D006096:Gramicidin; D002586:Cesium; D011188:Potassium