Figure 3.

Structural model of LFNG, showing the proximity of the mutated phenylalanine residue (orange) to the Mn²⁺ binding site (Mn²⁺ in purple). Directly interacting residues F196 and H198 are shown in cyan, and the nearby Mn²⁺-ligating residues D202 and D203 are in red. The position of the UDP-sugar donor group (green) and an acceptor sugar (yellow) are shown for reference. α-helices and β-sheets are colored in a gradient from dark blue (amino terminus) to red (carboxy terminus).