Structural aspects of nucleotide ligand binding by a bacterial 2H phosphoesterase

Myllykoski, Matti; Kursula, Petri

As the crystals obtained in the presence of substrate resulted in the structure of a product complex, we also modeled the likely substrate complex of LigT and 2 0 ,3 0 -cAMP, based on our earlier liganded complexes of CNPase [16] [17] [18] , coupled to manual docking and energy minimization. The predicted binding mode and interactions are very similar to those seen in CNPase. Compared to the product binding mode, His125 is not directly interacting with the substrate, but coordinates the nucleophilic water instead (Fig 3B) .