Table 3. List of peptides identified in the protect and label analysis of the binding sites for heparin in Fc rNRP-1.
The complete list of ions identified by MALDI-Q-TOF mass spectrometery is presented according to the descending intensity of the ions, along with their observed and theoretical masses with appropriate error values (expressed in ppm) and directly linked to the recognised sequences and their respective location within the Fc rNRP-1. The biotinylated lysines are indicated in bold. Assigned spectra are available in the Supplementary data (Fig. S5).
| Peptide | Mass experimental | Mass calculated | Error (ppm) | Sequence | Residues | Domain |
|---|---|---|---|---|---|---|
| 1 | 1800.96 | 1800.91 | 24.3 | VRIK(Biotin)PASWETGISM | 404–417 | b1 |
| 2 | 1494.76 | 1494.6464 | 76 | AGAFR(Acetyl)SDK(Biotin)C(Carbamidomethyl)GGT | 19–30 | a1 |
| 3 | 1926.02 | 1926.0953 | -39.1 | DK(Biotin)NISRKPGNVLKTL(Ammonium) | 822–836 | L2 |
| 4 | 2024.1 | 2024.0481 | 26.4 | TLPPSRDELTK(Biotin)NQVSL | 978–993 | IgG1 Fc |
| 5 | 2125.14 | 2125.0059 | 63.1 | VVVDVSHEDPEVK(Biotin)FNW | 890–905 | IgG1 Fc |
| 6 | 1452.74 | 1452.6358 | 68.5 | AGAFRSDK(Biotin)C(Carbamidomethyl)GGT | 19–30 | a1 |
| 7 | 1790.91 | 1790.8643 | 26.1 | TVDK(Biotin)SRWQQGNVF | 1039–1051 | IgG1 Fc |
| 8 | 1381.71 | 1381.6603 | 43.3 | NGK(Biotin)EYKCKVS | 943–951 | IgG1 Fc |
| 9 | 1516.72 | 1516.7464 | −14.7 | QVIFEGEIGK(Biotin)GN | 778–789 | c |
| 10 | 1811.92 | 1811.9069 | 7.25 | SQADENQK(Biotin)GK(Acetyl)VARL | 695-708 | c |
| 11 | 2074.06 | 2074.0109 | 28 | MVVGHQGDHWK(Biotin)EGRVL | 754–769 | c |
| 12 | 1182.65 | 1182.6452 | 4.05 | VRIK(Biotin)PASW | 404–411 | b1 |
| 13 | 1909 | 1909.0688 | −36 | DK(Biotin)NISRKPGNVLKTL | 822–836 | L2 |
| 14 | 1628.7 | 1628.6621 | 23.3 | HSYHPSEK(Biotin)CEW | 46–56 | a1 |
| 15 | 1364.69 | 1364.6337 | 41.3 | NGK(Biotin)EYKCKVS -NH3 | 943–951 | IgG1 Fc |