Enzymatic catalysis in crystals of E.coli Maltodextrin Phosphorylase

S. Geremia, M. Campagnolo, R. Schinzel, L.N. Johnson

The structures obtained before (MalP/Glc1P) and after catalysis (MalP/Glc1P soaked in G4 and MalP/Glc1P soaked in G5) have been used as frames of a molecular movie of the Maltodextrin Phosphorylase (MalP) enzyme. This movie reveals the relative positions of substrates in the catalytic channel and shows a minimal movement of the protein, mainly involving Arg569 residue that tracks the substrate phosphate.