The modelling of the ligand flavin adenine dinucleotide into p-hydroxybenzoate hydroxylase (PDB entry 1cc6
; Eppink et al., 1999) as depicted by the ArpNavigator GUI. (a) Following input of the experimental 2.2 Å resolution data and the protein model, a difference density map is automatically calculated and shown along with the `sparse grid' used for ligand building by the ARP/wARP `label-swapping' method. (b) The ensemble of models built prior to selection of the best-fitting ligand model. (c) The final ligand model after real-space refinement is output to the screen for viewing and further analysis where necessary.