Table 1.
Samples used for SAXS measurements and their composition
| NaCl, mM | Sample (concentration, mg/ml) | Volume fractions, % |
χ2 | R | ||
|---|---|---|---|---|---|---|
| Tetramer | Octamer | 32-mer | ||||
| 0 | K139C (4.2/7.5) | 100 ± 1 | 0 ± 0 | 0 ± 0 | 2.6 | 0.03 |
| WT (2/3) | 100 ± 3 | 0 ± 0 | 2 ± 2 | 0.8 | 0.08 | |
| WT (6.6/7.7) | 79 ± 5 | 0 ± 0 | 22 ± 1 | 1.1 | 0.04 | |
| 6 | K139C (4.5/6.6) | 74 ± 1 | 26 ± 1 | 0 ± 0 | 2.9 | 0.04 |
| 12 | K139C (4.5/6.6) | 34 ± 1 | 66 ± 1 | 0 ± 0 | 4.2 | 0.04 |
| 20 | K139C (1.6) | 3 ± 0 | 97 ± 1 | 0 ± 0 | 0.5 | 0.05 |
| K139C (2.5) | 1 ± 1 | 71 ± 5 | 29 ± 2 | 0.7 | 0.07 | |
| K139C (6.5) | 0 ± 0 | 46 ± 2 | 54 ± 1 | 1.4 | 0.05 | |
| K139C (18) | 0 ± 0 | 20 ± 1 | 80 ± 1 | 4.6 | 0.07 | |
| 50 | K139C (3.9/5.1)/WT (3.9/5.7) | 9 ± 1 | 2 ± 1 | 90 ± 1 | 3.6 | 0.05 |
| 75 | K139C (2.1/4/8/17) | 0 ± 0 | 0 ± 0 | 100 ± 1 | 1.2 | 0.06 |
| 100 | K139C (3.7/4.9)/WT (6.9) | 0 ± 0 | 0 ± 0 | 100 ± 3 | 1.5 | 0.08 |
The buffer used was 5 mM Tris·HCl, pH 8.4. Quasimonodisperse solutions used to build the tetramer, octamer, and the ULF models are shown in bold. In nearly all conditions, the SAXS data collected for the WT and the K139C mutant were not significantly different and are shown together. In most cases, no pronounced dependence of the SAXS curve on the sample concentration was present. For definitions of the goodness-of-fit χ2 and the R factor between the experimental data and calculated scattering see Supporting Text.