The thermal motions of the atoms in a dynamical simulation of ferrocytochrome c are geometrically decomposed into local and highly collective components, and the contributions of these components to the net motion are determined for different intervals of time. It is found that the atomic displaceme
Molecular dynamics of ferrocytochrome c: Anharmonicity of atomic displacements
β Scribed by Boryeu Mao; Michael R. Pear; J. A. McCammon; S. H. Northrup
- Publisher
- Wiley (John Wiley & Sons)
- Year
- 1982
- Tongue
- English
- Weight
- 544 KB
- Volume
- 21
- Category
- Article
- ISSN
- 0006-3525
No coin nor oath required. For personal study only.
β¦ Synopsis
Abstract
The atomic position distributions obtained from a 32βps molecularβdynamics simulation of tuna ferrocytochrome c at 297 K are analyzed in terms of their second, third, and fourth moments. NonβGaussian relations among these moments are found for the majority of atoms in the molecule, indicating anharmonicity in the effective potential functions for the atomic motions. Many atoms exhibit only slightly anharmonic mobility during the 32βps period, but about half of the atoms exhibit sizeable anharmonicity. For a typical atom, the anharmonic effects are largest for motions in the direction along which the largest displacements occur. Two classes of significantly anharmonic atoms are apparent: those whose effective potentials are distorted toward a squareβwell shape and those whose effective potentials have secondary minima corresponding to conformational substates.
π SIMILAR VOLUMES
The atomic motions from a molecular-dynamics simulation of yeast tRNAPhe are analyzed and compared with those observed in protein simulations. In general, the tRNA motions are of larger amplitude, they are more anisotropic, and they arise from potentials of mean force that are more anharmonic than i
Phonon dispersion relations for molecular (rare-gas) solids have been computed by an anharmonic central-force rigid-atom model. The model derives the intermolecular interaction from a two-piece four-parameter pair potential, includes zero-point vibrations through potential parameters by a self-consi