Table 4.

Allosteric model parameters for I696X and W697X mutants in the presence of 1 and 100 µM capsaicin

Channel1 µM100 µM
DPΔGoDPΔGo
kcal/molkcal/mol
TRPV13703,000−1.45NANANA
I696A1,400320.401,300320.45
I696V1,008460−0.781444600.33
I696L1311,800−0.46381,8000.25
I696M373480−0.211344800.38
I696H504720−0.76617200.46
W697Y302,2000.17509,500−0.96
W697H304,000−0.15187,200−0.21
W697V182,9000.31256,100−0.31
W697D1013,000−0.2582,3000.92
W697N108,5000.0366,3000.50
  • Normalized g-V curves in the presence of capsaicin were fitted to Eq. 3. For I696X and wild type, the values for the equilibrium constants were fixed to those obtained in the absence of capsaicin: Jo = 0.021, L = 5.0 × 10−4, Kd = 10−5, and zg = 0.6. For W697X mutants, these values were the same, except for zg = 0.80, which was taken from the Boltzmann fits. The value of E given by the analysis for all mutants was virtually 1 and, therefore, was kept constant to this value. NA, not applicable.