Hi Emmanuel, Perhaps a little more information ?
What was the Z-score and LLG in PHASER ? I take it the translation function solution is fairly well separated from the rest ? Are you sure the spacegroup is correct ? How complete is the model before refinement ? Not to be paranoid, but Hexagonal/Trigonal settings support merohedral twinning... best, Iain -----Original Message----- From: CCP4 bulletin board [mailto:[EMAIL PROTECTED] On Behalf Of Emmanuel Prata Sent: Friday, May 11, 2007 10:27 AM To: CCP4BB@JISCMAIL.AC.UK Subject: [ccp4bb]. . Dear all, I have a structure (with 6 dissulphide bridges) at fairly low resolution (3A) that I am trying to refine with Refmac. I've used phaser with a template with 72% sequence identity. RFZ was 3.4 and TFZ 6.6, without clashes, with 80.7% of completeness. Space group was p3121 (pointless) and Rmerge 0.12. When i tried refmac, Rfac drop to 24%, but Rfree only drop to 41%. Can anybody explain this fact? Thanks in advance, Emmanuel Prata de Souza