Check the space group. It may be orthorhombic with a pure rotational axis (e.g. P21212) or even monoclinic.
From: CCP4 bulletin board [mailto:[email protected]] On Behalf Of Polisetty Satya Dev Sent: Friday, March 17, 2017 9:51 AM To: [email protected] Subject: [EXTERNAL] [ccp4bb] No improvement in R-factor after Refmac. Dear all, I solved a structure at 2.0 A resolution with R-work and R-free values 0.25 and 0.32 respectively and I am stuck at Refmac step where there is no further reduction in R-factor. The above stated values were obtained after several rounds of manual refinement followed by refmac. There are also areas where electron density is missing around peptide backbone in one of the monomer in ASU. Can anyone please tell me how can I improve the electron density and R-factor. The structure solution was obtained using Phaser MR and here are the data statistics: Average unit cell: 81.95, 100.40, 156.96, 90.00, 90.00, 90.00, Space group: P212121, Completeness 99.5, Multiplicity 6.4, Four monomers per ASU. Solvent content: 47%. Thank you everyone, Satya Dev, JNCASR.
