Table 4.
Data collection and processing parameters for analysis of the SorT/SorU complex in solution by Small Angle X-ray Scattering (SAXS).
| Data collection parameters | |
| Instrument | SAXSess (Anton Paar) |
| Beam geometry | 10 mm slit |
| AH, LH (Å-1), GNOM beam geometry definition | 0.28, 0.12 |
| q-range measured (Å-1) | 0.01-0.400 |
| Exposure time (min) | 60 (4 x 15) |
| SorT2SorU2 concentration range (mg mL-1) | 2.75-5.5 |
| Temperature (ºC) | 10 |
| Structural parameters* | |
|
Rg (Å), I(0) (cm-1) from Guinier (desmeared data) q*Rg < 1.3 |
30.8 ± 0.4, 0.223 ± 0.002 |
|
Rg (Å), I(0) (cm-1) from P(r) (q-range 0.01 – 0.25 Å-1) |
32.0 ± 0.3, 0.235 ± 0.002 |
| dmax (Å) from P(r) | 110 |
| Molecular mass determination* | |
| Molecular mass Mrfrom Guinier I(0) (ratio with expected) | 108741 (0.984) |
| Molecular mass Mrfrom P(r) I(0) (ratio with expected) | 114593 (1.037) |
| SorT2SorU2 parameters calculated from sequence and chemical composition | |
| Molecular volume (Å3) | 134385 |
| Molecular weight Mr (Da) | 110556 |
| Partial specific volume (cm3 g-1) | 0.732 |
| Contrast (X-rays) (Δρ x 1010 cm-2) | 2.895 |
| Modeling results and validation | |
| Crystal structure Rg, dmax (Å) SorT/SorU2/SorT SorT |
31.3, 108 27.9, 99 |
| Crystal structure compare to desmeared I(q) (χ-value) SorT/SorU2/SorT (q-range 0.01 – 0.15 Å-1) SorT (q-range 0.01 – 0.15 Å-1) |
1.7 2.3 |
| Results from 10 ab initio shape restorations. P1 symmetry: Average molecular volume (Å3) Normalised spatial distribution (NSD) and NSD variation χ value for fit to desmeared data |
140800 0.508 (0.008) 1.8 |
| Software employed | |
| Calculation of expected Mr, △ρ and υ values | MULCh |
| Primary data reduction, I(q) vs q | SAXSQuant 1D |
| Desmearing | SAXSQuant |
| Guinier analysis | PRIMUS |
| P(r) analysis | GNOM |
| Model I(q) from crystal coordinates | CRYSOL |
| ab initio shape restorations | DAMMIN |
| 3D graphics representations | PYMOL |
*Reported for 2.75 mg ml-1 measurement.