Table 4.
Affinity measurement for OccJ and NocT towards natural octopine family members and octopine analogues. ITC experiments of NocT were not performed with lysopine and histopine.
| Ligand | F | ITC | ||||||
|---|---|---|---|---|---|---|---|---|
| Kd (µM) | Kd (µM) | N | Enthalpy (ΔH) (cal/mol) | Entropy (ΔS) (cal/mol/deg) | Entropic contribution (-TΔS) (cal/mol) | Free enthalpy (ΔG) (cal/mol) | ||
| OccJ | octopinic acid 
|
0.017 ± 0.003 | 0.038 ± 0.007 | 0.87 | −9547 | 1.40 | −410 | −9957 |
lysopine 
|
0.14 ± 0.01 | 0.11 ± 0.02 | 0.97 | −4832 | 15.2 | −4455 | −9287 | |
histopine 
|
33.1 ± 3.5 | 326 | 1.03 | −854 | 13 | −3810 | −4664 | |
homo-octopine 
|
0.23 ± 0.03 | 0.53 ± 0.04 | 0.93 | −7611 | 2.75 | −806 | −8417 | |
noroctopine 
|
0.19 ± 0.05 | 0.15 ± 0.01 | 1.02 | −4804 | 14.8 | −4367 | −9171 | |
| noroctopinic acid | 0.23 ± 0.4 | 0.15 ± 0.01 | 0.92 | −7202 | 6.60 | −1934 | −9136 | |
| homo-noroctopine | 4.63 ± 0.42 | 19.3 ± 1.4 | 1.01 | −4115 | 7.53 | −2207 | −6322 | |
| NocT | octopinic acid | 1.8 ± 0.3 | 4.4 ± 0.4 | 0.87 | −3658 | 12.0 | −3517 | −7175 |
| lysopine | 11.2 ± 3.5 | |||||||
| histopine | 84.4 ± 6.7 | |||||||
| homo-octopine | 5.4 ± 0.6 | 30.6 ± 2.1 | 0.86 | −3832 | 7.58 | −2222 | −6054 | |
| noroctopine | 33.4 ± 2.7 | 78 ± 9 | 0.9 | 872 | 21.8 | −6390 | −5518 | |
| noroctipinic acid | 19.3 ± 1.37 | 23 ± 5 | 0.92 | 620 | 23.3 | −6830 | −6210 | |
| homo-noroctopine | 21.3 ± 2.1 | 79 ± 14 | 0.75 | −1195 | 14.7 | −4309 | −5504 | |