Conformational transitions of AdK (with ligands) observed in LT-MD simulations. (a) Starting from the open state with both ATP and AMP, simulation O-ATP-AMP. (b) Starting from the open state with only ATP, simulation O-ATP. (c) Starting from the open state with only AMP, simulation O-AMP. (d) Starting from the closed state with both ATP and AMP, simulation C-ATP-AMP. More details can be found in Text S2, Table S3, and Figs. S7–S10. To see this figure in color, go online.