Fig. 3.

Nucleotide binding in WbmF, WbmG and WbmH. Proteins are oriented with the Rossmann domains in the lower part of each structure. Cartoons are used to represent protein backbone; bound nucleotides are shown as ball-and-stick and key protein side chains as sticks. The boxed panels show details of UMP-binding pockets in (a) His₆-WbmF, UDP co-crystal, (b) His₆-WbmG crystal soaked with UDP-glucose and (c) His₆-WbmH. In (a) and (b), UMP is shown as sticks, and spheres represent atoms within 3.5 Å of the bound nucleotide. Probable hydrogen-bonding interactions are shown as dashed lines. In (c) spheres represent ordered water molecules in this binding pocket. Carbon atoms are coloured rainbow for protein, white for bound nucleotides; oxygen atoms are coloured red; nitrogen is blue and phosphorus orange.