Table 4. AAV2 Viral Protein PTM Features Identified at 45K and 15K MS Resolution Analyzed by HILIC-FLR-MS.
| AAV capsid variant identity | AAV
observed mass (Da) |
AAV theoretical mass (Da) | Δmass
(ppm) |
||||
|---|---|---|---|---|---|---|---|
| 25 °C | 45 °C | 60 °Cb | 25 °C | 45 °C | 60 °Cb | ||
| 45k MS resolution | |||||||
| VP1 (1–734)Ac + 1x Ox | 81873.42 | 81873.77 | 81874.70 | 81870.89 | 30.9 | 35.1 | 46.4 |
| VP1 (1–734)Ac | 81855.10 | 81855.44 | 81855.34 | 81854.90 | 2.5 | 6.6 | 5.4 |
| VP2 (138–734) + 1x Ox | 66504.57 | 66505.84 | —c | 66503.90 | 10.0 | 29.1 | —c |
| VP2 (138–734) | 66487.25 | 66487.49 | 66487.55 | 66487.90 | 9.9 | 6.2 | 5.3 |
| VP3 (203–734)Ac + 2x Ox | 60006.63 | 60007.33 | 60007.61 | 60005.78 | 14.2 | 25.9 | 30.4 |
| VP3 (203–734)Ac + 1x Ox | 59991.52 | 59992.56 | 59992.27 | 59989.78 | 29.0 | 46.4 | 41.4 |
| VP3 (203–734)Ac | 59973.40 | 59973.62 | 59973.54 | 59973.78 | 6.3 | 2.7 | 4.1 |
| VP3 (203–734)Ac- ≈ 19.5 Da | 59953.83 | 59953.88 | 59954.11 | 59955.77 | 32.3 | 31.4 | 27.6 |
| VP3 (211–734)Ac | 59300.16 | —c | —c | 59301.03 | 14.7 | —c | —c |
| 15k MS resolution | |||||||
| VP1 (1–734)Ac + 1x Oxa | 81877.35 | 81875.45 | 81873.63 | 81870.89 | 78.9 | 55.7 | 33.4 |
| VP1 (1–734)Ac | 81856.81 | 81855.91 | 81856.11 | 81854.90 | 23.4 | 12.4 | 14.9 |
| VP2 (138–734) + 1x Oxa | 66507.47 | 66506.85 | 66507.42 | 66503.90 | 53.6 | 44.3 | 52.9 |
| VP2 (138–734) | 66487.53 | 66487.39 | 66487.82 | 66487.90 | 5.6 | 7.7 | 1.3 |
| unknown feature | —c | —c | 60173.24 | —c | —c | —c | —c |
| VP3 (203–734)Ac + 1x Ox | 59991.30 | 59991.47 | 59991.78 | 59989.78 | 25.2 | 28.1 | 33.3 |
| VP3 (203–734)Ac | 59972.86 | 59973.47 | 59973.49 | 59973.78 | 15.4 | 5.3 | 4.9 |
| VP3 (211–734)Ac | 59301.00 | 59301.03 | 59301.56 | 59301.03 | 0.5 | 0.6 | 9.0 |
a
Poor identification due to high background interference from mobile phase.
b
Identifications were found in a minimum of two of the replicates instead of all three replicates.
c
— feature was not identified during analysis.