Dynamic instability of liquidlike motions in a globular protein observed by inelastic neutron scattering

Inelastic neutron scattering was used to investigate liquidlike motions and the nature of a dynamic transition in myoglobin, a small globular protein. The signature of the transition is a strong enhancement of low-frequency density fluctuations and a corresponding decrease in elastic scattering above 180 K. It is shown that the line shape of the inelastic-scattering function approximates the scaling behavior predicted for a simple liquid by mode-coupling theories in the vicinity of the liquid-glass transition.