Table 1. Data Collection Statistics for Native Structure Determination.
| Data Set | Native | SeMet Derivative #1 | SeMet Derivative #2 | SeMet Derivative #3 | |||||
|---|---|---|---|---|---|---|---|---|---|
| Peaka | Inflection | Peak | Inflection | Remote | Peak | Inflection | Remote | ||
| Wavelength (Å) | 1.1808 | 0.9794 | 0.9797 | 0.9794 | 0.9797 | 0.9641 | 0.9794 | 0.9797 | 0.9641 |
| Number of unique reflections | 27999 | 33959 | 25264 | 30517 | 29663 | 24300 | 22928 | 24042 | 22768 |
| Completeness (%)b | 99.9 (99.6) | 84.3 (70.6) | 88.5 (78.3) | 92.8 (71.8) | 89.8 (61.5) | 94.0 (81.0) | 65.1 (53.7) | 73.3 (70.0) | 67.3 (54.0) |
| Resolution (Å) | 30-2.9 | 50-3.2 | 50-3.6 | 50-3.4 | 50-3.4 | ||||
| I/σb | 25.0 (3.5) | 7.9 (2.2) | 6.7 (2.4) | 4.8 (1.2) | 5.1 (1.1) | 5.5 (1.5) | 4.8 (1.3) | 5.1 (1.5) | 4.8 (1.3) |
| Rmergeb,c | .055 (41.0) | 0.083 (.39) | 0.098 (.36) | 0.167 (.64) | 0.161 (.67) | 0.141 (.55) | 0.125 (.51) | 0.135 (.52) | 0.130 (.50) |
| Isomorphous Rcullisd (centric/accentric) | 0.76/0.75 | - | 0.95/0.94 | 0.96/0.91 | 0.93/0.90 | 1.02/0.98 | 0.92/0.91 | 0.92/0.91 | 0.91/0.90 |
| Anomalous Rcullisd (accentric) | - | 0.79 | 0.96 | 0.87 | 0.97 | 0.96 | 0.93 | 0.99 | 0.96 |
| Isomorphous Phasing Powere (centric/accentric) | 0.82/0.88 | - | 0.29/0.31 | - | 0.33/0.33 | 0.24/0.26 | - | 0.21/0.24 | 0.22/0.25 |
| Anomalous Phasing Powere (accentric) | - | 1.15 | 0.5 | 0.73 | 0.41 | 0.44 | 0.58 | 0.32 | 0.36 |
| Figure of merit (centric/accentric) | 0.20/0.28 | ||||||||
|
| |||||||||
| Refinement statistics | 50-2.9 | ||||||||
| R | 23.3% for 24785 reflections | ||||||||
| Rfree | 28.6% for 2136 reflections | ||||||||
| Rms bond length, bond angles | 0.0067 Å, 1.14° | ||||||||
a
This data set was used as the reference data set in phase refinement using SHARP.
b
Numbers in parentheses are for the highest-resolution bins.
c
Rmerge = ΣhΣi |Ihi - 〈Ih〉 |/ΣhΣi Ihi
d
RCullis = Σh| |Fp(h) - FPH(h)| - |FHcalc(h)| | / Σh|Fp(h) - FPH(h) |, where FP, FPH and FH are the amplitudes of the native, SeMet derivatives, and Se atoms, respectively.
e
Phasing power = rms(FH/E), where E is the lack of closure error.