Systems Biology and Mathematical Modeling Group, Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany.|Central Metabolism Group, Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany, Consiglio per la Ricerca e la Sperimentazione in Agricoltura, Centro di ricerca per lOrticoltura, Pontecagnano (Salerno), Italy.|Central Metabolism Group, Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany.|Systems Biology and Mathematical Modeling Group, Max Planck Institute of Molecular Plant Physiology, Potsdam, Germany.