SBDS protein flexibility. SBDS molecules are superposed by domain II. The view is as in Figure 1 but rotated by ~90° around the vertical axis. Labels indicate domains I, II and III. a) Ribbon diagrams of two mthSBDS molecules present in the asymmetric unit (A, blue and B, yellow). b) Stereo view of Ca models of the two mthSBDS molecules (A, blue and B, yellow) and afSBDS ([PDB:1P9Q], red).