Table 1. Mass measurements from native MS analysis of PCAT1 samples.
| Sample | In UDM | In C8E4 | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Expected mass (Da) | Measured Mass ± SDa (Da) | Mass error (%)b | Measured Mass ± SDa (Da) | Mass error (%)b | |||||||
| wt PCAT1 dimer | 162,176 | 162,175 | ± | 1 | 0.0008 | - | 162,171 | ± | 1 | 0.003 | - |
| CtA | 10,207.9 | 10,206.5 | ± | 0.5 | 0.014 | 10,206.5 | ± | 0.3 | 0.014 | ||
| - | - | - | % Abun- dancec | - | - | % Abun- dancec | |||||
| C21A-PCAT1 dimer + 1 CtA | 172,320 | 172,337 | ± | 4 | 0.010 | 25 ± 2 | 172,341 | ± | 3 | 0.012 | 16 ± 2 |
| C21A-PCAT1 dimer + 2 CtA | 182,528 | 182,549 | ± | 3 | 0.012 | 75 ± 2 | 182,558 | ± | 6 | 0.017 | 84 ± 2 |
a From the average and S.D. of the mass values calculated from each charge state peak within a charge-state distribution (n ≥ 4 charge states).
b Mass accuracy measured by the relative difference between measured and expected masses divided by the expected mass.
c Based on relative peak intensities for the peak series corresponding to the 182 kDa and 172 kDa complexes within the same MS spectrum and corrected for gas-phase dissociation (see Figure 1—figure supplement 2 for more details) (n ≥ 3 conditions).