It's a P212121 dataset. I have used phaser to find four solution in ASU.
This is the phaser log file:
------------------------------------------------------------
PEUDO-TRANSLATIONAL NCS VECTOR
--------------------------------------------------------------
Space Group : P 21 21 21
Patterson Symmetry: P m m m
Resolution of All Data (Number): 2.45 49.00 (22968)
Resolution of Patterson (Number): 5.00 9.99 (2364)
There were 2 non-origin distinct peaks (i.e. more than 15 angstroms from the
origin)
<!--SUMMARY_BEGIN-->
84.1% origin: FRAC 0.500 0.000 0.250 (ORTH 32.0 0.0 32.2)
72.2% origin: FRAC 0.000 0.000 0.500 (ORTH 0.0 0.0 64.4)
<!--SUMMARY_END-->
More than one pseudo-translational ncs vector found
Correction factors will not be applied
PS: I have used phenix.xtrige and found the p-value of
pseudo-translational ncs is very little, which indicates the exist of
the pseudo-translational ncs. And no twin found in this dataset.
Now the problem is two in the four molecules of an ASU have worse
electron density than the other two molecules. And after rigidbody and
restraint refinement by refmac without "twin refinement", the R/Rfree
is a little high (0.33/0.36). And if I turn on the "twin refinement"
in refmac, the R/Rfree is 0.30/0.33.
So, my question is, there is not twin in my data but
pseudo-translational ncs, is it suitable to use "twin refinement" in
refmac, which has a good R/Rfree result.
Thanks a lot for your help.
Best wishes,
Qixu Cai
2012/7/31, Eleanor Dodson <eleanor.dod...@york.ac.uk>:
> More details - what do you mean by pesudo-translational symmetry ?
> Are there two molecules related by a translation vector? or its it
> something more complicated?
> Eleanor
>
> On 31 July 2012 10:47, Qixu Cai <caiq...@gmail.com> wrote:
>
>> Dear all,
>>
>> Can I use the "twin refinement" to refine the pesudo-translational
>> symmetry dataset?
>>
>> Thanks a lot for your help.
>>
>> Best wishes,
>>
>> Qixu Cai
>>
>
--
Qixu Cai
Email: caiq...@gmail.com
School of Life Sciences,
Xiamen University, Fujian, China
