List of residues forming the NBD–NBD contact interface
Numbers refer to positions of these residues in BSEP. Those that are common to all ABC family members are shown in bold. Residues, which were mutated and characterized in this study, are shown in italics. Deviant residues are shown in the fourth and eighth columns.
| Residue in BSEP | Motif | Amino Acids | Alternative Amino Acid (Transporter) | Residue in BSEP | Motif | Amino Acids | Alternative Amino Acid (Transporter) |
|---|---|---|---|---|---|---|---|
| NBD1 | NBD2 | ||||||
| 457 | Walker A | S | N (B2, B3, B5) | 1115 | Walker A | S | N (B3) |
| 458 | Walker A | G | 1116 | Walker A | G | ||
| 502a | Q-loop | S | G (B2, B3), P (B6, B7), E (B11) | 1161 | Q-loop | Q | |
| 503 | Q-loop | Q | 1162 | Q-loop | E | D (B6, B7) | |
| 504 | Q-loop | E | D (B6, B7) | 1220 | Signature | S | |
| 560 | Signature | S | A (B3) | 1221 | Signature | G | R (B11) |
| 563 | Signature | Q | E (B6, B7) | 1222 | Signature | G | |
| 584 | Walker B | E | D (B2), M (B11) | 1223 | Signature | Q | E (B6, B7, B11) |
| 587 | D-loop | S | 1226 | Signature | R | ||
| 588 | D-loop | A | S (B7) | 1244 | Walker B | E | |
| 589 | D-loop | L | 1247 | D-loop | S | ||
| 590 | D-loop | D | 1248 | D-loop | A | S (B7) | |
| 615 | H-loop | H | Q (B2) | 1250 | D-loop | D | |
| 616 | H-loop | R | H (B2) | 1275 | H-loop | H | |
| 617 | H-loop | L | 1276 | H-loop | R | ||
| 1277 | H-loop | L | |||||
↵a Depending on the rotamer, this residue is predicted to interact with either ICL4 or the Mg2+ ion.