Figure 7: Model for ATPlid closure in AKe.
From: Overlap between folding and functional energy landscapes for adenylate kinase conformational change
Relative free-energy differences between open and closed ATPlid conformations in the presence of saturating ATP concentration for WT (a) and the M2 variant (b). The relative change in free energy (ΔΔGconf) is calculated from Kconf values of 1.5 and 124 (124 equals the minimum value that accounts for the increased ATP-binding affinity in M1 and M2 compared with WT) for WT and the M2 variant. The y axis in (a) and (b) is set arbitrarily such that the absolute values of the free energy for open, closed and transition state (TS‡) structures may in fact differ for the two enzymes. (c) Structural model of the conformational change in the ATPlid in the presence of bound ATP. The ATP complex is represented with yeast AKe in complex with the non-hydrolysable ATP analogue AMPPCF2P45. The structures going from open to partially unfolded to closed are arranged as a function of the reaction coordinate. The relative positions of the WT and the M1, M2 variants are indicated on the reaction coordinate and should be interpreted as a qualitative measure of the distance to the transition state.
