Table 5.
Characteristic tryptic peptides to determine signal peptide (position 1–28) within the identified hPRL variants.
| Calc. [M+H]+ | Position | Characteristic tryptic peptide sequence | Observed [M+H]+ |
|---|---|---|---|
| 505.2803 | 1–4 | MNIK | – |
| 1060.5608 | 1–9 | MNIKGSPWK | + |
| 3930.1893 | 1–38 | MNIKGSPWKGSLLLLLVSNL LLCQSVAPLPICPGGAAR | – |
| 574.2983 | 5–9 | GSPWK | – |
| 3443.9268 | 5–38 | GSPWKGSLLLLLVSNLLLCQ SVAPLPICPGGAAR | – |
| 2888.6463 | 10–38 | GSLLLLLVSNLLLCQSVAPL PICPGGAAR | – |
| 3589.0154 | 10–44 | GSLLLLLVSNLLLCQSVAPL PICPGGAARCQVTLR | – |
| 954.5189 | 29–38 | LPICPGGAAR | – |
| 1654.8879 | 29–44 | LPICPGGAARCQVTLR | – |
| 2301.1954 | 29–49 | LPICPGGAARCQVTLRDLFD R | – |
+, this peptide ion was observed with mass spectrometry in each MS spectrum. -, this peptide was not observed with mass spectrometry.