Dynamical properties and energy landscape of simple globular proteins

Analysis of dynamic properties of a simple globular protein, myoglobin, has demonstrated that it possesses a hierarchically organized energy landscape. It shows two types of specific protein motions, besides vibrations: 1) individual motions of small atomic groups — transitions between conformational substates (CS) of the lower tier 2, and 2) cooperative motions of secondary structure elements ( α-helices) — transitions between CS of the upper tier 1. The profile of macromolecule dynamic properties is highly heterogeneous. Only vibrations occur near the active center. The number of CS grows towards the periphery where specific type 1 and 2 motions become predominant. Such a picture is consistent with the concept of a protein as 'a random copolymer slightly edited in the vicinity of the active center'.