TABLE 4.
Physicochemical characterization of synthetic peptides
| Peptide | Average calculated massa | Observed massb | RTc | ϵ280d |
|---|---|---|---|---|
| Da | Da | min | m−1·cm−1 | |
| ProTx-II | 3826.7 | 3825.2 ± 0.2 | 25.4 | 23,865 |
| [K/R]ProTx-II | 3966.7 | 3966.4 ± 0.3 | 26.6 | 23,865 |
| [E17K]ProTx-II | 3825.7 | 3825.6 ± 0.2 | 25.5 | 23,865 |
| [K/R,E17K]ProTx-II | 3965.8 | 3965.2 ± 0.1 | 26.4 | 23,865 |
| [W5Y]ProTx-II | 3803.6 | 3803.3 ± 0.1 | 24.0 | 19,855 |
| [W7Y]ProTx-II | 3803.6 | 3803.5 ± 0.3 | 25.4 | 19,855 |
| [W24Y]ProTx-II | 3803.6 | 3803.4 ± 0.2 | 24.2 | 19,855 |
| [W30Y]ProTx-II | 3803.6 | 3803.4 ± 0.2 | 24.5 | 19,855 |
a Average calculated mass from the amino acid sequence is shown.
b Observed mass was obtained from m/z from ESI-MS.
c Retention time (RT) was determined using analytical HPLC with 2%·min−1 gradient of solvent B (90% acetonitrile, 0.1% trifluoroacetic acid) against solvent A (0.1% trifluoroacetic acid) starting from 1% solvent B.
d Coefficient extinction at 280 nm (ϵ280) calculated based on contribution of disulfide bonds and Tyr and Trp residues.