Figure 5.

Mg²⁺ coordination sphere (top) and catecholate (bottom) structural properties in the M5 QM/MM model across the reaction coordinate. At top, the median, averaged distance is reported as dashed lines for N170 (green), D141 and D169 (blue), and water (WAT, gray) as a reference for the CAT O(H) (dark gray) and CAT O^- (red) distances to Mg²⁺ across the reaction coordinate. At bottom, catechol hydrogen atom distance to neighboring E199 (dark blue) and to the catechol oxygen atom (dark green) are plotted along the reaction coordinate. The remaining quantities are the median values obtained at 0.01 Å increments and averaged over a 0.1 Å window with the range of variations shown as a shaded region. A schematic of E199, Mg²⁺, and CAT is shown in inset at bottom.