Table 1. Data collection and refinement statistics.
| Data collection | Holo ASM | Pt derivative | Phosphocholine | Olipudase alfa |
|---|---|---|---|---|
| X-ray wavelength (Å) | 1.2830 | 1.0721 | 1.5418 | 1.2825 |
| Resolution (Å) | 43.81–2.25 (2.33–2.25) | 42.33–2.43 (2.52–2.43) | 31.18–2.50 (2.64–2.50) | 45.00–3.65 (3.74–3.65) |
| Space group | P6422 | P6422 | P6422 | I222 |
| No. of reflections | 88030 | 68691 | 33985 | 118574 |
| Cell dimensions | ||||
| a, b, c (Å) | 132.5, 132.5, 189.8 | 132.2, 132.2, 189.3 | 131.6, 131.6, 188.6 | 191.0, 230.9, 252.3 |
| α, β, γ (°) | 90.0, 90.0, 120.0 | 90.0, 90.0, 120.0 | 90.0, 90.0, 120.0 | 90.0, 90.0, 90.0 |
| I/σ(I) | 22.9 (1.9) | 22.1 (2.0) | 12.6 (3.2) | 7.44 (0.34) |
| Rmerge | 0.092 (0.732) | 0.081 (0.735) | 0.200 (0.822) | 0.229 (5.35) |
| Completeness (%) | 99.5 (94.9) | 99.0 (90.9) | 99.9 (100.0) | 98.9 (86.3) |
| Redundancy | 10.3 (5.0) | 7.3 (4.9) | 17.3 (13.9) | 6.9 (5.4) |
| CC1/2 in highest shell | 0.669 | 0.743 | 0.852 | 0.108 |
| Phasing and refinement | ||||
| Phasing figure of merit | — | 0.251 | — | — |
| Rwork/Rfree | 0.184/0.203 | 0.190/0.222 | 0.248/0.254 | |
| Monomers per asymmetric unit | 1 | 1 | 1 | 3 |
| Composition per asymmetric unit | ||||
| Amino acid/sugar | 527/14 | 527/13 | 1581/29 | |
| Water/SO4 | 177/11 | 261/11 | 0//0 | |
| Zn/Phosphocholine | 2/0 | 2/1 | 6/0 | |
| rmsd | ||||
| Bond (Å) | 0.009 | 0.018 | 0.013 | |
| Angle (°) | 0.902 | 0.885 | 0.931 | |
| Ramachandran plot (favoured/allowed/outlier) | 96.4/3.6/0.0 | 95.4/4.6/0.0 | 95.6/4.2/0.2 |
ASM, acid sphingomyelinase; rmsd, root mean square deviation.
Holo ASM and Pt derivative are anomalous data collected at Zn peak and Pt L-III edge, respectively. Phosphocholine data set is non-anomalous. Olipudase Alfa data set is collected at Zn peak. Values in parentheses are for the highest-resolution shell.