Figure 3

Ligands electronic density map and Mg²⁺ coordination. 2fo-fc electronic density map of thiamine contoured at 1 sigma (A) and coordination of each Mg²⁺ ion in the TPK/thiamine complex (B-C). Fo-Fc electronic density map contoured at 1.5 sigma (displayed in green) of TPNP (D) with Mg²⁺ and PO4^3-. This map was computed using the refined structure where all ligands have been removed. Coordination of each Mg²⁺ ion in the TPK/thiamine-PNP complex (E-G). Magnesium are represented as white spheres, water molecules as cyan spheres, oxygen atoms are in red, nitrogen in blue and carbon in green. Mg²⁺ coordinations are marked with magenta dashed lines.