Table 2. Structures of α-conotoxin PnIA analogs.
| α-Conotoxin PnIA analogs | Amino acid sequences | Molecular weight (МН+, Da) |
|
|---|---|---|---|
| calculated | measured | ||
| PnIA | GCCSLPPCAANNPDYC* | 1623.8 | — |
| PnIA[R9] | GCCSLPPCRANNPDYC* | 1708.9 | 1708.1 |
| PnIA[R9, L10] | GCCSLPPCRLNNPDYC* | 1751.0 | 1750.2 |
| PnIA[R5, R9, L10, R14] | GCCSRPPCRLNNPRYC* | 1835.1 | 1834.3 |
The asterisk (*) shows the amidated C terminus. As in the natural α-conotoxin PnIA, disulfide bonds in all peptides were formed between Cys2–Cys8 and Cys3–Cys16 residues using orthogonal protecting groups. The substitutions introduced in the analogs are marked underlined.