Figure 1. The galactose binding sites in the EW29 galactose binding domain (residue 131 to residue 260 in EW29).

Galactose binding sites 1 and 2 correspond to the α- and γ-subdomains, respectively. Each of them is shown to bind to lactose via the galactose residue. The two side chains of residues (K132 and C243) that were selected for replacements are also shown.