Table III.
Trypsin Cleavage Products of the CNBr Fragments C5 and C6
| Peptide fraction | Peptide mass (nonreduced)a | Peptide mass (reduced)a | Δ Mass | Trypsin cleavage fragment | Sequence | Peptide mass (reduced)a | Peptide mass (reduced/ alkylated)a | Δ Mass |
|---|---|---|---|---|---|---|---|---|
| A | 3339.6 | 3343.5 | 4 | C5T3 | NLEEVEHC123VEHR | 1622.72 | 1679.72 | 57.0 |
| C5T6 | DAC150RGM | 667.2b | ND | |||||
| C6T1 | LC155GFGAVC161ER | 1053.5 | 1168.26 | 115.1 | ||||
| B | 3305.7 | 3312.5 | 7 | C6T4 | TAC180PVVVAPVC188 GSDYTYSNEC199ELK | 2763.2 | 2934.55 | 171.34 |
| C6T9 | GPC220GSK | 547.2 | ND | |||||
| C6T2c | SPTDPSQASC173V C175K | 1321.6 | ||||||
| C6T5c | AQC206NQQR | 846.4 |
All Peptide masses are given in Da. Individual fragments are labeled sequentially. Fraction A consists of C5T3, C5T6, and C6T1, whereas fraction B comprises C6T4 and C6T9, respectively. The peptides C6T2 and C6T5 containing cysteine residues Cys173, Cys175, and Cys206 could not be isolated. The calculated masses are given as monoisotopic values of the singly protonated peptides.
a
Molecular mass was calculated based on combined theoretical mass of individual trypsin fragments.
b
The oxidation and subsequent hydroxymethylation of the C-terminal Met adds +16Da to the peptide mass of 651.25 Da.
c
CNBr-trypsin fragments that could not be isolated.