Greetings all, My lab is working on a 3.2Å resolution structure with 6 NCS copies of an antibody Fab fragment with insertions in its CDR loops. The residue numbers of CDR loop H3, for example, include 100A, 100B, etc. in each of the heavy chains (Kabat numbering). There are observable differences between NCS copies in parts of the model due to crystal contacts and so forth, so we want to exclude those residues from the NCS. Phenix.refine, when given NCS restraints like the example below, produces a result with much higher R/Rfree values than when the same structure was run with "normal" continuous numbering (R/Rfree of .26/.30 compared to .21/.26 before changing to Kabat numbering). Reference selection: chain H and (resseq 1:100A or resseq 100H:113) Restrained selection: chain I and (resseq 1:100A or resseq 100H:113) Phenix version is 1.6.4-486. Any thoughts on what might be causing this or how to account for the non-standard numbers in NCS restraints? Thanks, Jared Sampson -- Jared Sampson Xiangpeng Kong Lab NYU Langone Medical Center New York, NY 10016 212-263-7898 ------------------------------------------------------------ This email message, including any attachments, is for the sole use of the intended recipient(s) and may contain information that is proprietary, confidential, and exempt from disclosure under applicable law. Any unauthorized review, use, disclosure, or distribution is prohibited. If you have received this email in error please notify the sender by return email and delete the original message. Please note, the recipient should check this email and any attachments for the presence of viruses. The organization accepts no liability for any damage caused by any virus transmitted by this email. =================================