Check your Rfree flag. Phenix and refmac may use different flag. Have a look 
into log file. If percentage of Rfree reflections is 95% then flags need to be 
swapped.

Garib

On 9 Dec 2011, at 02:50, Mark J van Raaij wrote:

> are you sure that you are using the original input intensities for the REFMAC 
> map calculation (and the refinement run) and not the output ones of the 
> (previous) run?
> if you are not, you may have model bias, and Rfree can be fooled, especially 
> with NCS (if you have it).
> 
> - or perhaps anisotropic B-factor refinement (if you are using it), works 
> better in REFMAC than PHENIX?
> 
> Mark J van Raaij
> Laboratorio M-4
> Dpto de Estructura de Macromoleculas
> Centro Nacional de Biotecnologia - CSIC
> c/Darwin 3
> E-28049 Madrid, Spain
> tel. (+34) 91 585 4616
> http://www.cnb.csic.es/content/research/macromolecular/mvraaij
> 
> 
> 
> 
> 
> On 8 Dec 2011, at 18:36, Christopher Browning wrote:
> 
>> Dear All,
>> 
>> Question: Has anybody ever refined the same structure using PHENIX and
>> then tried REFMAC to see what happens?
>> 
>> I did and I stumbled on something funny. I'm refining a structure at
>> 1.1A resolution which was solved with Iodine phasing using PHENIX
>> AutoSolve. Got a great map and the structure was built almost
>> completely. I had to build a few residues myself, and using the
>> published sequence, I started filling in the residues, but as I came
>> nearer the N-terminus, it looked like the density did not match residues
>> from the sequence. I kept the residues as in the sequence, but as you
>> can see from the PHENIX refined picture (below is the link) it still
>> looks like the amino acid sequence in the crystal does not match the
>> published protein sequence.
>> 
>> Out of interest I refined the same file in REFMAC, and now the electron
>> density is correct, and the sequence of the amino acids in the crystal
>> matches the published sequence (see link for picture below). Not only
>> that..... my R/Rfree improved (16.5/19 for PHENIX, 10/18 for REFMAC). 
>> 
>> I've also refined the occupancies of the iodide, however the the output
>> FO-FC map from PHENIX complains and the REFMAC map is fine.....
>> 
>> How can this be and what causes this?
>> 
>> Link for the pictures:
>> Both maps are at identical Sigma levels in both pictures.
>> PHENIX: http://dl.dropbox.com/u/51868657/PHENIX_refined.png
>> REFMAC: http://dl.dropbox.com/u/51868657/REFMAC_refined.png
>> 
>> Cheers,
>> 
>> Chris Browning
>> 
>> 
>> 
>> -- 
>> Dr. Christopher Browning
>> Post-Doctor to Prof. Petr Leiman
>> EPFL
>> BSP-416
>> 1015 Lausanne
>> Switzerland
>> Tel: 0041 (0) 02 16 93 04 40

Garib N Murshudov 
Structural Studies Division
MRC Laboratory of Molecular Biology
Hills Road 
Cambridge 
CB2 0QH UK
Email: ga...@mrc-lmb.cam.ac.uk 
Web http://www.mrc-lmb.cam.ac.uk



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