Gramicidin channels and pores.

MODEL NOMENCLATURE 129 POLYMORPHISM OF GRAMICIDIN . . 133 Identification of Multiple Conformations in Solution 133 One Predominant Conformation Is Present in Membranes 137 Ion Binding Affects Gramicidin Conformations ... 139 PHYSICAL NATURE OF THE CONFORMERS 141 The Pore Is a Double Helix 1 41 The Channel Is a Helical Dimer 144 fon Binding Sites in the Pore and in the Channel 147