Conformation of gramicidin S

A molecular conformation of Gramicidin S was derived on the basis of conformational calculations taking into account the available experimental data. The conformation is characterized by a dyad axis which relates the two chemically equivalent halves of the molecule and contains four hydrogen bonds; other structural features agree with experimental results. X Ray Crystallographic evidences for the relative position of the Ornithine residues is also reported which supports an important feature of the structure of Gramicidin S.