Table 2.
Peptides derived from influenza A nucleoprotein and detected by MALDI-TOF MS.
| H1N1 strains | Observed [M+H]+ | H3N2 strains | Observed [M+H]+ |
|---|---|---|---|
| SALILR | 672.4 | SALILR | 672.4 |
| NLPFER | 775.4 | DS | 2184.1 |
| QDATEIR | 832.4 | QNATEIR | 831.4 |
| AMMDQVR | 850.4 | AMVDQVR | 818.4 |
| KTGGPIYR | 891.5 | KTGGPIYR | 891.5 |
| SRYWAIR | 951.5 | SGYWAIR | 852.4 |
| GKFQTAAQR | 1006.5 | GKFQTAAQR | 1006.5 |
| MVLSAFDER | 1067.5 | MVLSAFDER | 1067.5 |
| GVGTIAMELIR | 1159.7 | ND | – |
| LIQNSITIER | 1186.7 | DS | 2207.2 |
| MVLSAFDERR | 1223.6 | MVLSAFDERR | 1223.6 |
| MCSLMQGSTLPR | 1380.6 | MCSLMQGSTLPR | 1380.6 |
| ELILYDKEEIR | 1420.7 | ELVLYDKEEIR | 1406.7 |
| ATVMAAFSGNNEGR | 1424.6 | STIMAAFTGNTEGR | 1455.7 |
| ELILYDKEEIRR | 1576.9 | ELVLYDKEEIRR | 1562.8 |
| NPGNAEIEDLIFLAR | 1671.9 | NPGNAEIEDLIFLAR | 1671.9 |
| ASAGQISVQPTFSVQR | 1675.8 | ASAGQTSVQPTFSVQR | 1663.9 |
| MMESAKPEDLSFQGR | 1725.8 | MMEGAKPEEVSFR | 1510.7 |
| SQLVWMACHSAAFEDLR | 2020.9 | SQLVWMACHSAAFEDLR | 2020.9 |
| ESRNPGNAEIEDLIFLAR | 2044.0 | ESRNPGNAEIEDLIFLAR | 2044.0 |
| SYEQMETGGERQDATEIR | 2099.9 | SYEQMETDGDRQNATEIR | 2142.9 |
| SCLPACVYGLAVASGHDFER | 2209.0 | ND | |
| DS | 775.4; 1424.6 | NLPFEKSTIMAAFTGNTEGR | 2184.1 |
| DS | 1186.7; 1067.5 | LIQNSLTIEKMVLSAFDER | 2207.2 |
| LLQNSQVVSLMRPNENPAHK | 2275.2 | LLQNSQIYSLIRPNENPAHK | 2335.2 |
| GVQIASNENVETMDSNTLELR | 2320.2 | GVQIASNENMDNMGSSTLELR | 2266.0 |
Peptides with a S/N of ≥6 are listed. These peptides were identified in tested viral strains at titers of 1 × 109 genome copies in the total volume of each sample, deposited onto a MALDI plate and analyzed.
ND, peptide not detected.
DS, detected sequence in the tested strains but in another peptide due to missed cleavage by trypsin.