Table 4. Binding data for the interaction of AcAChBP with (−)-nicotine, (+)-anatoxin-a, (−)-cytisine and (−)-hosieine-A.

Mean thermodynamic parameters are derived from ITC; the dissociation constant K _d1 was determined from ITC and K _d2 from fluorescence measurements. The standard error for each measurement is given (n = 3).

Ligand	N (sites)	ΔG (kcal mol−1)	ΔH (kcal mol−1)	−TΔS (kcal mol−1)	K d1 (μM)	K d2 (μM)
(−)-Nicotine	0.4 ± 0.03	−7.7 ± 0.1	−17.8 ± 0.9	10.0 ± 0.9	2.30 ± 0.19	0.41 ± 0.01
(−)-Nicotine†	0.6	−8.3	−12.5	4.2	0.835
(+)-Anatoxin-a	0.5 ± 0.02	−8.9 ± 0.1	−12.5 ± 0.2	3.6 ± 0.2	0.30 ± 0.03	0.15 ± 0.01
(−)-Cytisine†	0.6	−7.9	−13.3	5.4	1.6
(−)-Cytisine‡	0.6 ± 0.01	−8.6 ± 0.3	−15.2 ± 1.2	6.6 ± 1.4	0.60 ± 0.03
(−)-Hosieine-A	0.7 ± 0.03	−10.4 ± 0.2	−8.9 ± −0.1	−1.5 ± 0.3	0.025 ± 0.005	0.040 ± 0.001

^†Data from Rucktooa et al. (2012 ▸) are presented for comparison.

^‡Data from Davis et al. (2020 ▸) are presented for comparison.