Molecular dynamics of ferrocytochrome c: Magnitude and anisotropy of atomic displacements

Two computer simulations of the atomic motion in tuna ferrocytochrome c have been carried out. The average structures and the structural correlations of the magnitudes of the atomic position fluctuations are in substantial agreement with recent X-ray diffraction results, particularly for the protein interior. The simulations show, however, that the atomic displacements are quite anisotropic. The degree of anisotropy and the preferred directions of atomic displacement exhibit correlations with structural features of the protein.