Free energies of ADP.Pi complexes from MMPBSA 33 calculations. Energy decomposition identifies entities that stabilize the leaving Pi ion most strongly: the Mg 2+ ion and the side chain of K251. Electrostatic terms but not solvation terms are responsible for energy differences between the states. Data are presented as mean values. Error bars represent s.e. Statistics are derived from n = 250 conformations extracted from a single MD simulation.
