Table III. An annotated set of glycopeptide assignments identified by LC-MS/MS.
A total of 64 species were assigned, and relevant analytical information has been tabulated. A high degree of sialylated glycopeptides were observed with 1–3 sialic acid residues, and a total of 23 distinct glycan compositions were observed. For the glycan composition entry, the following notations were used: H, Hexose; N, N-acetylhexosamine; F, fucose; A, N-acetylneuraminic acid. Each glycan assignment was supported by a sub −20 ppm mass error in the MS/MS spectra.
| OFFGEL Fraction | RT | Precursor m/z | z | MH+ | Glycan composition | Peptide MH+ | Glycan fragment mass | No. 13C | ppm error for glycan loss |
|---|---|---|---|---|---|---|---|---|---|
| min | |||||||||
| 1 | 5.0 | 1041.3996 | 4 | 4162.5766 | H6N5A3 | 1301.6098 | 2862.9702 | 2 | −12.7 |
| 1 | 9.8 | 949.3801 | 4 | 3794.4986 | H5N4A2 | 1588.7300 | 2205.7700 | 1 | −2.4 |
| 1 | 19.4 | 1025.4285 | 3 | 3074.2710 | H5N4A2 | 868.5042 | 2205.7668 | 1 | −3.9 |
| 1 | 21.9 | 961.9293 | 4 | 3844.6954 | H5N4A2 | 1638.9270 | 2205.7730 | 1 | −1.1 |
| 2 | 5.4 | 960.6302 | 4 | 3839.4990 | H5N4A2 | 1632.7377 | 2206.7613 | 2 | −7.9 |
| 2 | 35.6 | 1375.9322 | 3 | 4125.7821 | H5N4F1A1 | 2065.0513 | 2060.7308 | 1 | −0.3 |
| 5 | 9.2 | 1001.4104 | 3 | 3002.2167 | H5N4A2 | 796.4458 | 2205.7709 | 1 | −2.0 |
| 5 | 9.3 | 1048.7663 | 3 | 3144.2844 | H5N4A2 | 937.5064 | 2206.7780 | 2 | −0.3 |
| 5 | 15.7 | 1088.4593 | 3 | 3263.3634 | H7N4A1 | 1025.6070 | 2237.7564 | 0 | −11.9 |
| 6 | 4.9 | 877.5990 | 4 | 3507.3742 | H5N4A2 | 1301.6400 | 2205.7342 | 1 | −18.7 |
| 6 | 7.4 | 935.6323 | 4 | 3739.5074 | H5N4F1A2 | 1386.6700 | 2352.8374 | 2 | 3.3 |
| 6 | 11.0 | 960.3997 | 4 | 3838.5770 | H5N4F1A2 | 1485.7400 | 2352.8370 | 2 | 3.1 |
| 6 | 13.5 | 980.7674 | 3 | 2940.2877 | H5N4A1 | 1025.6100 | 1914.6777 | 1 | 3.8 |
| 6 | 14.1 | 1055.7649 | 3 | 3165.2802 | H5N4A2 | 959.5118 | 2205.7684 | 1 | −3.2 |
| 6 | 16.1 | 1078.1338 | 3 | 3232.3869 | H5N4F2A1 | 1025.6093 | 2206.7776 | 1 | −2.2 |
| 6 | 16.2 | 1126.4807 | 3 | 3377.4276 | H5N4F1A2 | 1025.6100 | 2351.8176 | 1 | −3.9 |
| 6 | 16.9 | 1029.9271 | 4 | 4116.6866 | H5N4F1A2 | 1763.8567 | 2352.8299 | 2 | 0.1 |
| 7 | 9.9 | 1126.4680 | 3 | 3377.3895 | H5N4F1A1 | 1316.6485 | 2060.7410 | 1 | 4.7 |
| 7 | 12.0 | 997.1022 | 3 | 2989.2921 | H6N3A1 | 1115.6331 | 1873.6590 | 1 | 3.0 |
| 7 | 12.1 | 943.0851 | 3 | 2827.2408 | H5N3A1 | 1115.6363 | 1711.6045 | 1 | 1.8 |
| 7 | 13.5 | 938.9036 | 4 | 3752.5926 | H5N4A2 | 1546.8113 | 2205.7813 | 1 | 2.7 |
| 7 | 14.1 | 1055.4285 | 3 | 3164.2710 | H5N4A2 | 959.5068 | 2204.7642 | 0 | −3.6 |
| 7 | 19.5 | 995.9446 | 4 | 3980.7566 | H5N4A2 | 1775.9700 | 2204.7866 | 0 | 6.6 |
| 7 | 20.4 | 1027.4584 | 4 | 4106.8118 | H5N4A2 | 1902.0600 | 2204.7518 | 0 | −9.2 |
| 7 | 21.8 | 1003.9319 | 4 | 4012.7058 | H5N4A2 | 1806.9400 | 2205.7658 | 1 | −4.3 |
| 7 | 23.2 | 988.7003 | 4 | 3951.7794 | H5N4A1 | 2037.1035 | 1914.6759 | 1 | 2.9 |
| 7 | 24.6 | 1061.2232 | 4 | 4241.8710 | H5N4A2 | 2037.0967 | 2204.7743 | 0 | 1.0 |
| 7 | 26.1 | 912.0044 | 5 | 4555.9929 | H5N4A2 | 2349.2200 | 2206.7729 | 2 | −2.6 |
| 7 | 28.5 | 1034.2194 | 4 | 4133.8558 | H5N4A2 | 1927.0600 | 2206.7958 | 2 | 7.7 |
| 9 | 9.4 | 767.9207 | 5 | 3835.5744 | H5N5A2 | 1425.7300 | 2409.8444 | 2 | −5.9 |
| 10 | 6.1 | 935.1452 | 4 | 3737.5590 | H5N4A2 | 1530.7865 | 2206.7725 | 2 | −2.8 |
| 10 | 6.6 | 787.1215 | 5 | 3931.5784 | H5N4A2 | 1725.8100 | 2205.7684 | 1 | −3.1 |
| 10 | 26.6 | 914.4295 | 4 | 3654.6962 | H5N4A2 | 1448.9200 | 2205.7762 | 1 | 0.4 |
| 16 | 7.2 | 1073.4713 | 3 | 3218.3994 | H5N4F1A1 | 1158.6700 | 2059.7294 | 0 | 0.7 |
| 16 | 8.6 | 1007.7892 | 3 | 3021.3531 | H5N4F1A1 | 961.6200 | 2059.7331 | 0 | 2.5 |
| 16 | 13.9 | 1029.4527 | 3 | 3086.3436 | H5N4F1A1 | 1024.6000 | 2061.7436 | 2 | 4.3 |
| 16 | 15.5 | 1047.9351 | 4 | 4188.7186 | H6N5F1A1 | 1762.8487 | 2425.8699 | 1 | 2.7 |
| 16 | 15.6 | 956.4007 | 4 | 3822.5810 | H5N4F1A1 | 1762.8530 | 2059.7280 | 0 | 0.0 |
| 16 | 27.4 | 1085.1565 | 3 | 3253.4550 | H5N4F1A1 | 1193.7246 | 2059.7304 | 0 | 1.1 |
| 16 | 28.2 | 909.6679 | 4 | 3635.6498 | H5N4F1A1 | 1574.9200 | 2060.7298 | 1 | −0.8 |
| 16 | 30.6 | 1291.9146 | 3 | 3873.7293 | H5N4F1A1 | 1812.9990 | 2060.7303 | 1 | −0.5 |
| 16 | 32.1 | 962.6926 | 4 | 3847.7486 | H6N5F1A1 | 1422.8871 | 2424.8615 | 0 | 0.6 |
| 16 | 32.5 | 977.4430 | 4 | 3906.7502 | H6N6A1 | 1422.8785 | 2483.8717 | 2 | −9.7 |
| 16 | 32.6 | 936.6859 | 4 | 3743.7218 | H5N6A1 | 1422.8845 | 2320.8373 | 1 | -0.9 |
| 16 | 32.9 | 1229.9039 | 3 | 3687.6972 | H5N5F1A1 | 1422.8881 | 2264.8091 | 2 | −2.0 |
| 16 | 32.9 | 929.9304 | 4 | 3716.6998 | H5N3F2A2 | 1422.8800 | 2293.8198 | 0 | 10.8 |
| 16 | 32.9 | 934.6821 | 4 | 3735.7066 | H5N4F1A1 | 1673.9700 | 2061.7366 | 2 | 0.9 |
| 16 | 34.4 | 873.6599 | 4 | 3491.6178 | H5N4F1 | 1721.9700 | 1769.6478 | 1 | 7.0 |
| 16 | 36.4 | 946.6840 | 4 | 3783.7142 | H5N4F1A1 | 1721.9600 | 2061.7542 | 2 | 9.5 |
| 17 | 7.5 | 821.1278 | 4 | 3281.4894 | H5N4F2A1 | 1074.7200 | 2206.7694 | 1 | −9.0 |
| 17 | 13.7 | 865.3820 | 4 | 3458.5062 | H5N5F2 | 1339.7295 | 2118.7767 | 1 | 4.9 |
| 17 | 13.8 | 1104.4873 | 3 | 3311.4474 | H5N5F1 | 1339.7293 | 1971.7181 | 0 | 3.1 |
| 17 | 14.0 | 920.4036 | 4 | 3678.5926 | H6N6F1 | 1339.7300 | 2338.8626 | 2 | 5.1 |
| 17 | 14.2 | 883.8876 | 4 | 3532.5286 | H6N6 | 1339.7259 | 2192.8027 | 2 | 15.0 |
| 17 | 15.4 | 993.1662 | 4 | 3969.6430 | H5N4F2A1 | 1762.8503 | 2206.7927 | 1 | 1.5 |
| 17 | 17.0 | 1009.7729 | 3 | 3027.3042 | H5N5F1 | 1054.5865 | 1972.7177 | 1 | 1.2 |
| 17 | 37.6 | 1020.7279 | 4 | 4079.8898 | H6N6F1 | 1742.0423 | 2337.8475 | 1 | 0.1 |
| 18 | 9.6 | 898.9125 | 4 | 3592.6282 | H5N4F2A1 | 1386.8573 | 2205.7709 | 0 | −3.7 |
| 19 | 11.7 | 878.4148 | 4 | 3510.6374 | H5N4A2 | 1303.8825 | 2206.7549 | 2 | −10.8 |
| 23 | 14.3 | 1058.6978 | 4 | 4231.7694 | H5N6F3 | 1762.8571 | 2468.9123 | 2 | 5.1 |
| 23 | 14.6 | 971.1642 | 4 | 3881.6350 | H5N5F2 | 1762.8519 | 2118.7831 | 1 | 7.9 |