Figure 3.

The motional patterns of the first four lowest-frequency deformational modes: mode 7 (a), 8 (b), 9 (c), and 10 (d). Note that the first six modes are zero modes corresponding to global translation and rotation of the entire molecule. For each mode, two opposite conformations (left and right) during harmonic vibration are shown to illustrate the direction of the motion. The amplitude of the motion was arbitrarily chosen for visual clarity. The arrows are used to indicate the directions of the motions. The larger circles in a and b indicate the intersubunit hinge, and the smaller circles in c and d indicate the intrasubunit hinges. The dotted lines in d indicate the longest axes of the subunits.