Figure 4.

(a) Superposition of the data set 1 structures of AcNiR-big and AcNiR-small coloured by r.m.s.d. between the structures from low values (blue) to high values (red). (b) Superposition (using monomers A) of trimers generated by crystal symmetry for data set 1 of AcNiR-small (orange) and AcNiR-big (cyan). The view is down the threefold axis. While the structures of individual monomers are very similar, structural changes across the trimer are larger and are related to the change in unit-cell volume. The loop regions (residues 186–193) are shown in dark grey.