Figure 8.

Conformational changes in the half-of-the-sites models. Divergent stereograms showing a snapshot of the HS1 model (a) and the HS2 model (b) superimposed upon the catalytic core of the starting structure. The view is down the twofold axis as in Figure 1(a). Monomer 1 is coloured in blue and light blue, while monomer 2 is shown in shades of pink. The darker shade is used to represent the starting structure, while the final snapshot is shown in light pink or light blue. In both cases the dimers are oriented such that the active site containing ATP (shown in ball and stick representation, in black) is the left hand subunit. Very similar conformational changes are observed for the two half-of-the-sites models. Conformational changes can be observed in the motif 2 loop (labelled M2), the C2-C3 loop (labelled C2), flipping loop, an insertion domain loop and the 4-helix bundles of both monomers (locations as given in Figure 1). In the left hand monomer, the helical bundle rotates slightly toward ATP while in the right hand monomer it rotates away from the cleft. The N-terminal domain rotates as a rigid body in both monomers. This figure was created using Molscript [58] and RASTER3D [59].