title: 5-A Fourier map of gramicidin A phased by deuterium-hydrogen solvent difference neutron diffraction.
abstract: Crystals of ion-free gramicidin A (P212121: a = 24.61, b = 32.28, c = 32.52) have been investigated using neutron diffraction. A difference analysis of crystals soaked in ethanol/H2O as opposed to ethanol-d6/D2O has led to single isomorphous replacement Fourier projections of the structure at 5-A resolution. The gramicidin dimer appears to be a 32-A-long cylinder oriented parallel to the c-axis in these crystals.
mesh_terms: D003461:Crystallography / Q000379:methods; D003903:Deuterium; D005583:Fourier Analysis; D006096:Gramicidin; D006859:Hydrogen; D008958:Models, Molecular; D009502:Neutrons; D012997:Solvents
chemical_list: D012997:Solvents; D006096:Gramicidin; D006859:Hydrogen; D003903:Deuterium