Table 2. Summary of residues from TcSKR1 and TcSKR2 that are involved in the binding of sulfakinin peptides through polar interactions.
| Peptide# | Sequence | Amino acid* | TcSKR1 |
TcSKR2 |
||
|---|---|---|---|---|---|---|
| Region& | Amino acid* | Region& | Amino acid* | |||
| sSK | FDDY(SO3H)GHMRF-NH2 | F1 | — | — | ECL2 | W194 |
| H4 | TM VI | Y438 | ECL2 | K189 | ||
| Y6 | TM V | D221 | — | — | ||
| ECL 2 | E206 | — | — | |||
| D7 | TM V | N217 | — | — | ||
| D8 | TM V | N217 | — | — | ||
| F9 | — | — | TM VII | K351 | ||
| nsSK | FDDYGHMRF-NH2 | F1 | ECL 2 | R199 | ECL 2 | E200 |
| H4 | TM VI | Y438 | ECL 2 | R191 | ||
| Y6 | ECL 2 | E206 | — | — | ||
| D7 | TM V | N217 | ECL 3 | S342 | ||
| D8 | ECL 2 | W207 | — | — | ||
#sSK, sulfated sulfakinin; nsSK, nonsulfated sulfakinin.
*Amino acid is represented with the single-letter code. The following numerical indicates the position from the N-terminus of a peptide or protein.
&TM, transmembrane region; ECL, extracellular loop.
–no interaction detected.