Thank you very much for all comments. Certainly it will help me a lot!
I will compare the maps at different resolutions, reprocess the data with 
another program, looking out the mosaicity and multiplicity, and I will try to 
use all data if it is possible.
Some answers: there is no ice on crystal; I had a good prediction of the spots 
in the indexed patterns (but I will process the data again with another program 
and observe it better); Xtriage said that I don´t have twinning; I run Zanuda 
due to the possibility of pseudo translation, but it said that the space group 
seems to be correct; the multiplicity is Overall- 10.3  InnerShell - 9.5 
OuterShell - 10.2; the diffraction spots are smeared.
Bests regards,
Juliana

Juliana Ferreira de Oliveira
Brazilian Laboratory of Biosciences - LNBio
Brazilian Center for Research in Energy and Materials - CNPEM
Campinas-SP, Brazil


De: CCP4 bulletin board [mailto:CCP4BB@JISCMAIL.AC.UK] Em nome de Xiao Lei
Enviada em: quinta-feira, 30 de março de 2017 08:44
Para: CCP4BB@JISCMAIL.AC.UK
Assunto: Re: [ccp4bb] Large number of outliers in the dataset

This case is encouraging to me that a structure can be solved with such high 
mosaicity (in your report is 1.9). I wonder how the diffraction looks like (I 
imagine spots smearing or streak). With such high mosaicity, the unit cell 
dimension and space group determination is highly likely not accurate. I 
usually lose hope of a dataset with average mosaicity above 1.3 and I would not 
process any high mosaic data, but from your case it seems 2.6A cutoff you get a 
very nice solution.  It seems the  data processing software (Imosflm or XDS) 
nowadays can handle with high mosaic data well.





On Wed, Mar 29, 2017 at 11:00 AM, Gianluca Santoni 
<gianluca.sant...@esrf.fr<mailto:gianluca.sant...@esrf.fr>> wrote:
In addition to what Nicolas has pointed out, is it quite suspicious to me that 
you have the same multiplicity in the high resolution shell as in the low 
resolution.

On Mar 29, 2017 18:17, Nicolas FOOS 
<nicolas.f...@esrf.fr<mailto:nicolas.f...@esrf.fr>> wrote:

Dear Juliana,

all the statistics presented here looks good in terms of resolution cut (maybe 
I will be less sever). For me the point is about the mosaicity you report 1.90 
it's high in my opinion. How looks you images? I am wondering if the indexation 
is really right. And maybe the complain of Xtriage about outlier is due to this 
high mosaicity. What is the diagnostic of Xtriage in terms of possible 
twinning? I am also wondering about a pseudo translation.
Maybe try to re-processed your data in this direction.

Hope to help.

Nicolas

Nicolas Foos

PhD

Structural Biology Group

European Synchrotron Radiation Facility (E.S.R.F)

71, avenue des Martyrs

CS 40220

38043 GRENOBLE Cedex 9

+33 (0)6 76 88 14 87<tel:+33%206%2076%2088%2014%2087>

+33 (0)4 76 88 45 19<tel:+33%204%2076%2088%2045%2019>
On 29/03/2017 17:56, Mark J van Raaij wrote:
To be really convinced I think you should also compare the maps at 2.6 and 2.3 
Å. If the 2.3 Å map looks better, go for it. If it doesn’t look better, perhaps 
you are adding noise, but the I/sigma and CC1/2 values suggest you aren’t.
Perhaps try 2.5 and 2.4 Å also.
And perhaps remove a well-ordered aa from the input model, refine at different 
resolutions and compare the difference maps for that aa. Or calculate omit maps 
at different resolutions and compare those.

Mark J van Raaij
Dpto de Estructura de Macromoleculas
Centro Nacional de Biotecnologia - CSIC
calle Darwin 3
E-28049 Madrid, Spain
tel. (+34) 91 585 4616<tel:+34%20915%2085%2046%2016>
http://wwwuser.cnb.csic.es/~mjvanraaij<http://wwwuser.cnb.csic.es/%7Emjvanraaij>

On 29 Mar 2017, at 17:44, Phil Evans 
<p...@mrc-lmb.cam.ac.uk<mailto:p...@mrc-lmb.cam.ac.uk>> wrote:

It is not clear to me why you believe that cutting the resolution of the data 
would improve your model (which after all is the aim of refinement). At the 
edge CC(1/2) and I/sigI are perfectly respectable, and there doesn’t seem to be 
anything wrong with the Wilson plot. Th R-factor will of course be higher if 
you include more weak data, but minimising R is _not_ the aim of refinement. 
You should keep all the data

I don’t know what xtriage means by “large number of outliers”: perhaps someone 
else can explain

Phil


On 29 Mar 2017, at 14:54, Juliana Ferreira de Oliveira 
<juliana.olive...@lnbio.cnpem.br<mailto:juliana.olive...@lnbio.cnpem.br>> wrote:

Hello,
I have one dataset at 2.3 Å (probably it can be better, I/σ = 2.1 and CC1/2 = 
0.779, the summary data is below), but when I perform Xtriage analysis it says 
that “There are a large number of outliers in the data”. The space group is 
P212121. When I refine the MR solution the Rfree stops around 30% and it 
doesn´t decrease (in fact if I continue refining it starts to increase).
The Wilson plot graph is not fitting very well between 2.3 and 2.6 Å:

<image001.jpg>

So I decided to cut the data at 2.6A and Xtriage analysis doesn’t notify about 
outliers anymore. I could refine the MR solution very well, the final Rwork is 
0.2427 and Rfree = 0.2730 and validation on Phenix results in a good structure.
I run Zanuda to confirm the space group and it says that the space group 
assignment seems to be correct.
Do you think that I can improve my structure and solve it at 2.3 Å or better? 
Or I can finish it with 2.6 Å? To publish at 2.6 Å I need to justify the 
resolution cut, right? What should I say?
Thank you for your help!
Regards,
Juliana

Summary data:
Overall            InnerShell      OuterShell
Low resolution limit                          51.51              51.51          
     2.42
High resolution limit                          2.30                 7.27        
        2.30
Rmerge                                               0.147               0.054  
             0.487
Rmerge in top intensity bin                0.080               -                
      -
Rmeas (within I+/I-)                          0.155               0.057         
      0.516
Rmeas (all I+ & I-)                            0.155               0.057        
       0.516
Rpim (within I+/I-)                            0.048               0.017        
       0.164
Rpim (all I+ & I-)                              0.048               0.017       
        0.164
Fractional partial bias                        -0.006             -0.003        
     0.146
Total number of observations            83988             2907                
11885
Total number unique                          8145                307            
      1167
Mean((I)/sd(I))                                   9.3                   23.9    
             2.1
Mn(I) half-set correlation CC(1/2)    0.991               0.998               
0.779
Completeness                                     99.9                 99.5      
           100.0
Multiplicity                                        10.3                 9.5    
               10.2

Average unit cell: 37.57 51.51 88.75 90.00 90.00 90.00
Space group: P212121
Average mosaicity: 1.90


Juliana Ferreira de Oliveira
Brazilian Laboratory of Biosciences - LNBio
Brazilian Center for Research in Energy and Materials - CNPEM
Campinas-SP, Brazil




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