Fig. 12.

Expected outcomes for Val to Gly mutation effects on ligand binding. The simplest case of a two-state ensemble is displayed. In the molecular picture, red indicates folded parts of the protein and yellow indicates unfolded parts. Note that the diagrams and equations are general and may apply to many enzyme–ligand systems, although they describe the specific case of AK(e) and its LID domain as discussed in the text. The equations are restatements and syntheses of equations previously discussed in the text: symbol Ω, denoting conformational degrees of freedom, was introduced in (1) and (2), K_conf and ΔG_conf in (7) and (8). Case II (orange) is the energetic region where the greatest experimentally observed changes would occur, and the approximately 5% unfolded LID domain for wild-type AK(e) places it in this region