Well, the first thing I note is that P6(3) is a polar space group.
Hence what I would do myself is the following:
take your crystal 'number 1' (as a reference);
take the results of XDS for crystal number 2 (XDS_ASCII.HKL) and reindex it;
try to see which of the original XDS_ASCII or the reindexed XDS_ASCII
file gives you the lowest R-sym values, the one with the lowest Rsym's
has consistent indexing with your 'reference' crystal 1 - normally
somewhere in the XDS output (forgot where) there is a reindexing card
mentioned
repeat with crystal 3;
Then you know what is consistent w.r.t. crystal 1. So you take the 3
files that are appropriate and repeat the XSCALE scaling.
It may very well be that you do not have any twinning but that you have
not consistently indexed the 3 data sets. Unless you have already taken
care of consistent indexing but didn't say (write) it.
HTH,
Fred.
On 19/10/12 13:17, Iris Gawarzewski wrote:
Hello everybody,
I collected datasets with a resolution to 2.8A from 3 crystal grown
in the same condition. The space group seems to be P63. Statistic of
XSCALE.LP
SUBSET OF INTENSITY DATA WITH SIGNAL/NOISE >= -3.0 AS FUNCTION OF
RESOLUTION
RESOLUTION NUMBER OF REFLECTIONS COMPLETENESS R-FACTOR
R-FACTOR COMPARED I/SIGMA R-meas CC(1/2) Anomal SigAno Nano
LIMIT OBSERVED UNIQUE POSSIBLE OF DATA observed
expected Corr
10.00 1023 173 204 84.8% 7.4%
14.1% 1023 10.86 8.1% 99.5* -28 0.422 156
6.00 4199 704 709 99.3% 11.1%
15.1% 4199 10.43 12.1% 99.1* -25 0.515 640
4.00 12401 2131 2137 99.7% 15.5%
15.5% 12400 9.91 17.0% 97.7* -18 0.684 1893
3.50 8429 1486 1486 100.0% 18.3%
18.0% 8426 8.10 20.1% 96.4* -8 0.788 1259
3.30 4630 842 842 100.0% 23.0%
22.3% 4627 6.59 25.5% 94.5* -13 0.768 686
3.10 6057 1121 1121 100.0% 28.3%
26.3% 6053 5.50 31.4% 93.6* -3 0.829 882
3.00 3527 664 664 100.0% 33.7%
34.2% 3524 4.56 37.5% 86.8* 6 0.827 502
2.90 3961 756 756 100.0% 48.4%
49.5% 3956 3.24 53.8% 82.7* 2 0.784 549
2.80 2140 699 862 81.1% 31.6%
37.4% 2057 2.51 37.7% 87.0* 2 0.789 178
total 46367 8576 8781 97.7% 17.2%
18.1% 46265 7.15 19.0% 98.2* -9 0.730 6745
I tried Xtriage and got the following:
merohedral twin operator
twin law: h,-h-k,-l
Britton plot: 0.423
H-test: 0.439
Maximum Likelihood Method: 0.457
I have a model with the sequence of my protein and did Phaser_MR
(Z-score around 4... I know that this is quiet bad...). This solution
I refined with phenix.refinement using the twin law from Xtriage.
Rfree is around 0.44 best but the model looks weird...
Greetings,
Iris
___________________________________
Iris Gawarzewski
PhD student
Arbeitskreis Schmitt
Institut für Biochemie
Geb. 26.32.03.21
Heinrich-Heine-Universität Düsseldorf
Universitätsstr. 1
40225 Düsseldorf
-Germany-
Tel: 0049-211-81-13577
--
Fred. Vellieux (B.Sc., Ph.D., hdr)
IBS / ELMA
41 rue Jules Horowitz
F-38027 Grenoble Cedex 01
Tel: +33 438789605
Fax: +33 438785494
