Hi All,
I have a data set that was collected to about 2.2A, which I have processed in either P21 (to 2.4 A) or C2221 (2.25A).
I am unsure which space group is more correct.
I have a higher symmetry space group with higher resolution and average statistics or a lower symmetry space group with lower resolution and great statistics.
The statistics provided by aimless below.
Any help would be hugely appreciated.
Thanks,
P21
AIMLESS
P21 and cut the data to 2.4A for a Mn I/sd > 2.
Average unit cell: 74.68 130 129.2 90 106.8 90
Overall InnerShell OuterShell
Low resolution limit 48.09 48.09 2.44
High resolution limit 2.40 13.15 2.40
Rmerge (within I+/I-) 0.085 0.038 0.581
Rmerge (all I+ and I-) 0.099 0.042 0.687
Rmeas (within I+/I-) 0.117 0.053 0.792
Rmeas (all I+ & I-) 0.116 0.050 0.798
Rpim (within I+/I-) 0.080 0.037 0.534
Rpim (all I+ & I-) 0.059 0.026 0.405
Rmerge in top intensity bin 0.045 - -
Total number of observations 352569 2057 17425
Total number unique 92184 569 4538
Mean((I)/sd(I)) 9.6 23.6 2.0
Mn(I) half-set correlation CC(1/2) 0.995 0.995 0.648
Completeness 100.0 97.2 100.0
Multiplicity 3.8 3.6 3.8
PHENIX – XTRIAGE
One possible pseudo merohedral twin operator
2-fold axis
h, -k, -h-l
<I**2>/<I>**2 = 2.032
<F>**2/<F**2> = 0.787
<|E**2-1|> = 0.734
<|L|>, <L**2> = 0.490, 0.321
Multivariate Z score L-test = 0.616
NZ test = Maximum deviation acentric = 0.007
Maximum deviation centric = 0.051
L test = Mean L = 0.490
Estimated twin fraction:
0.450 (Britton analyses)
0.477 (H-test)
0.478 (Maximum likelihood method)
Likely point group of the data is C 2 2 2
Analysis of the systematic absences indicates a number of likely space group candidates:
C 2 2 21
Patterson analysis of peak with length larger than 15 Angstrom:
Frac. Cood = 0.00, 0.166, 0.00
Distance to origin = 21.530
Height (origin = 100) = 3.787
p-value (height) = 9.991e-01
Final REFMAC refinement in P21
Rfactor = 0.2391
Rfree = 0.2674
After multiple rounds of refinement the twinning information is:
Twin domains = 2
Twin fractions = 0.5201, 0.4799
FINAL refinement PHENIX – P21
Rwork = 0.1637
Rfree = 0.1938
Twin fraction = 0.5 for twin operator h, -k, -h-l
Ramachandran outliers = 0.1%
Rotamer outliers = 3.6%
C-beta outliers = 0
C2221
AIMLESS
Cut the data back to 2.25 for a Mn I/sd >2.
Average unit cell: 74.68 247.4 130 90 90 90
Overall InnerShell OuterShell
Low resolution limit 48.09 48.09 2.31
High resolution limit 2.25 9.81 2.25
Rmerge (within I+/I-) 0.117 0.044 0.984
Rmerge (all I+ and I-) 0.126 0.046 1.068
Rmeas (within I+/I-) 0.136 0.051 1.145
Rmeas (all I+ & I-) 0.135 0.050 1.147
Rpim (within I+/I-) 0.069 0.026 0.577
Rpim (all I+ & I-) 0.050 0.019 0.417
Rmerge in top intensity bin 0.050 - -
Total number of observations 427886 5201 33337
Total number unique 57553 788 4433
Mean((I)/sd(I)) 11.4 32.6 2.0
Mn(I) half-set correlation CC(1/2) 0.997 0.997 0.668
Completeness 100.0 98.9 100.0
Multiplicity 7.4 6.6 7.5
First round of refinement - REFMAC – C2221
Rfactor = 0.2132
Rfree = 0.2443
Final refinement round - PHENIX – C2221
Rwork = 0.1853
Rfree = 0.2330
Ramachandran outliers = 0.1%
Rotamer outliers = 7.1%
C-beta outliers = 0