Fig. 5.
Distance dependence of coupling free energies between CRIPT and PDZ3 or PSG. The coupling free energies were plotted versus CαCα distance between the mutated residues in PDZ3 and CRIPT, respectively, for the six different allosteric networks: (A) PDZ3:CRIPTP-2 6 AA, (B) PDZ3:CRIPTP-3 6 AA, (C) PSG:CRIPTP-2 6 AA, (D) PSG:CRIPTP-3 6 AA, (E) PDZ3:CRIPTP-3 15 AA, and (F) PSG:CRIPTP-3 15 AA. The red horizontal line divides negative from positive coupling free energies. (G) The absolute number of all coupling free energies |∆∆∆Gc| from our double-mutant cycles in PDZ3 and PSG show no significant distance dependence, as illustrated by the exponential fit (distance constant dc = 21 ± 11 Å).