Gpc-1 crystal packing in selected dehydration states. The view is along the unit-cell a axis. The asymmetric unit and symmetry-related molecules are shown as Cα traces coloured by chain (A, green; B, blue; C, red; D, yellow). The unit-cell boxes, arrows and b and c unit-cell parameters are coloured by dehydration state: (a) control (no dehydration), blue; (b) 27 min, green; (c) 60 min, yellow; (d) 81 min, orange; (e) 105 min, red. Coloured arrows show the improvement in the intermolecular packing with dehydration.