Fig. 3.

A. The PfTrx-Px2 dimer with subunits coloured in purple and red. This figure was made using the program ccp4mg (Potterton et al., 2004).

B. Orthogonal view to A to show the intersubunit disulphide bridges.

C. Electron density in the vicinity of the intermolecular cystine. The 2F_obs − F_calc, α_calc map is contoured at the 1 σ level. The chains are coloured in cyan and green and the dual conformation of the resolving cysteine from chain B is evident.

D. Ribbon diagram showing the active site disulphide in the context of the Cp loop (red) and the C-terminal tail (blue).