Figure 4

Homology models of LmCitP and LlMelP. The substrate binding sites of KpCitS (a), and of homologous models of LmCitP (b) and LlMelP (c). Residues involved in substrate interaction are labeled. Hydrogen bonds and ionic interactions are shown by dashed lines. Backbone oxygens and nitrogens interacting with the substrate are not drawn. (S)-malates are shown as orange ball-and-stick models. The structures of the citrates superimposed on the malates are drawn as empty black sticks.