Table 5.
Residues involved in the docking of S-(+)-citalopram (escitalopram) to the agonist binding sites at the h(α9)2(α10)3 AChR.
| Orthosteric Site | 1 | 2 | 3 | ||
|---|---|---|---|---|---|
| TBE (Kcal / mol) | −15.22 | −14.85 | −12.13 | ||
| RMSD (Mean / Var) | 1.75 / 0.14 | 2.58 / 0.019 | 2.34 / 0.15 | Homologous residues* | |
| Secondary Structure | Subunit and Residues | ||||
| (−)α9 | (−)α9 | (−)α10 | (−)β4 | ||
| β1 Sheet | T34 | ||||
| Q36 | Q36 | E36 | Q38 | ||
| β2 Sheet | W57(−) | W57(−) | |||
| R59 (−) | R59(−) | R59(−) | K61 | ||
| N60 | |||||
| I61 | I61 | E61 | E63 | ||
| β3 Sheet | S79 | ||||
| R81 | R81 | R81 | R83 | ||
| β5 Sheet | V111(−) | V111(−) | V111(−) | I113 | |
| R113(−) | |||||
| β6 Sheet | T119(−) | T119(−) | R119(−) | L121 | |
| W120 | W120 | ||||
| D121(−) | D121(−) | D121(−) | L123 | ||
| (+)α10 | (+)α10 | (+)α10 | (+)α9 | (+)α3 | |
| β4-β5 Loop | Y95(+) | Y95(+) | Y95(+) | Y95 | Y93 |
| β7 Sheet | S150 | S150 | S150 | S150 | S148 |
| β7-β8 Loop | W151(+) | W151(+) | W151(+) | W151 | W149 |
| T152 | T152 | ||||
| G154 | G154 | G154 | N154 | D152 | |
| β9-β10 loop | Y192 | Y192 | Y192 | Y192 | Y190 |
| G193 | G193 | G193 | G193 | N191 | |
| C194(+) | C194(+) | C194(+) | C194 | C192 | |
| C195(+) | C195(+) | C195(+) | C195 | C193 | |
| S196 | S196 | S196 | S196 | E194 | |
| E197 | E197 | E197 | E197 | E195 | |
| β10 Sheet | Y199(+) | Y199(+) | Y199(+) | Y199 | Y197 |
Bold: residues forming H-bonds; Italics: residues forming cation-π interactions.
Principal (+) or complementary (−) canonical component.
*
The homologous residues at α3 and β4 subunits are also included for comparative purposes.