Dear Vincent, The easiest thing for you to do right now in the CCP4 context is to run Molrep, with the flag for PTS turned on. If that works and gives a clear solution, that's great. If not, then I'd suggest downloading a recent version of Phenix and trying the new version of Phaser that handles translational NCS, as in yesterday's discussion.
I don't think there's an advantage to reindexing, unless you have some reason to suspect that the true space group is not C2. In some cases, if the translation is close enough to a lattice translation, you can assume an exact lattice translation and reindex in a smaller cell, throwing away the weak half of the data, but I think the y-component of your translation is too far from zero for that to be a reasonable alternative. Best wishes, Randy Read On 13 Mar 2012, at 09:21, vincent Chaptal wrote: > Dear ccp4, > > I have a case of PTS and wonder what's the best strategy to handle my data. > > I processed my data in C2 with a=161 b=109 c=225 beta=104. The data in 97% > complete to 3,8A. > xtriage detected a 40% peak in the patterson at fractional coordinates > x=-0,001 y=0,055 z=0,5. > > I want to try to phase using MR. > Should I: > - leave the data in C2 (fully complete) and specify the program to use PST. > - expand from C2 to P1 and run using PST. > - re-index in P1 (a=98 b=97 c=225, alpha=78 beta=78, gamma=68) with only ca. > 80% completeness, and specify PST. > > before shooting more crystals to increase compleness and going for HA > phasing, i was wondering if i could do something with what i have. > thank you for your input. > vincent > > > -- > Vincent Chaptal, PhD > Institut de Biologie et Chimie des Protéines > Drug-resistance modulation and mechanism Laboratory > 7 passage du Vercors > 69007 LYON > FRANCE > +33 4 37 65 29 01 > http://www.ibcp.fr > ------ Randy J. Read Department of Haematology, University of Cambridge Cambridge Institute for Medical Research Tel: + 44 1223 336500 Wellcome Trust/MRC Building Fax: + 44 1223 336827 Hills Road E-mail: rj...@cam.ac.uk Cambridge CB2 0XY, U.K. www-structmed.cimr.cam.ac.uk
