Fig. 4.

The UDP-binding pockets are shown for (a) His₆-WbmF, soaked with UDP and (b) the His₆-WbmG, UDP co-crystal. Spheres represent atoms within 3.5 Å of the bound UDP; NAD indicates the nicotinamide ring of the NAD cofactor. (c) dTDP-glucose bound in the active site of a D128N, E129Q mutant of dTDP-glucose 4,6-dehydratase DesIV from S. venezuelae (PDB ID 1R6D).²³ The substrate-binding pockets are all shown from the same angle to enable comparison of the relative positions of the UDP diphosphates in (a) and (b) with the phosphates in dTDP-glucose in (c).