Mass Spectrometry of Big ET-1, ET-2, and ET-3 Derived Peptides Separated by HPLC
| Substrate . | HPLC Peptides . | Mass Spectrometry (Daltons) . | Predicted Amino Acids . | |
|---|---|---|---|---|
| Determined . | Theory . | |||
| Big ET-1 (1-38) | A | 4,284.5 | 4,283.0 | 1-38 |
| B | 2,494.6 | 2,492.0 | 1-21 | |
| C | 1,810.3 | 1,809.0 | 22-38 | |
| Big ET-2 (1-37) | A | 1,658.7 | 1,648.81 | 22-37 |
| 1,445.4* | 1,446.57 | 24-37 | ||
| B | 4,185.1 | 4,183.76 | 1-37 | |
| C | 2,546.4 | 2,546.97 | 1-21 | |
| Big ET-3 (1-41) | A | 2,301.3 | 2,299.55 | 22-41 |
| B | 2,645.2 | 2,643.1 | 1-21 | |
| Substrate . | HPLC Peptides . | Mass Spectrometry (Daltons) . | Predicted Amino Acids . | |
|---|---|---|---|---|
| Determined . | Theory . | |||
| Big ET-1 (1-38) | A | 4,284.5 | 4,283.0 | 1-38 |
| B | 2,494.6 | 2,492.0 | 1-21 | |
| C | 1,810.3 | 1,809.0 | 22-38 | |
| Big ET-2 (1-37) | A | 1,658.7 | 1,648.81 | 22-37 |
| 1,445.4* | 1,446.57 | 24-37 | ||
| B | 4,185.1 | 4,183.76 | 1-37 | |
| C | 2,546.4 | 2,546.97 | 1-21 | |
| Big ET-3 (1-41) | A | 2,301.3 | 2,299.55 | 22-41 |
| B | 2,645.2 | 2,643.1 | 1-21 | |
Mass spectrometry determined the presence of at least 3 components in peak A derived from big ET-2.
Small relative to the mass at 1,658.7.