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Hi Kyle, Are you refining with TLS? If so, then the default output will be the residual B-factors. To get the full B-factors you need to add the TLS component to the residual B's. This can be done by re-running your refmac job with the keyword TLSO ADDU Note that this version of refmac will also add your waters to TLS groups by default unless you give it the keyword TLSD waters Exclude So unless you included this keyword, then re-running refmac with your same input file and the TLSO ADDU keyword is the only way to ensure that your waters are converted to full B's as the CCP4 program TLSANL cannot do this since the TLS definitions in TLSOUT and the PDB header are not updated with regards to which waters were assigned to different TLS groups. Also, if you use the keyword TLSO ADDU, you should not use this PDB file as input to your next round of refinement unless you also use reset the B factors with the BFACtor SET ## keyword since refmac expects residual B's on the input file. I am not sure how many of these keywords are accessible via the ccp4i interface or if you have to add them via the run and view command file option if you use ccp4i. Regards, Mitch ------------------------------- From: CCP4 bulletin board [mailto:[log in to unmask]] On Behalf Of Kyle Dolan Sent: Friday, May 07, 2010 3:12 PM To: [log in to unmask] Subject: [ccp4bb] Unusually low B factors after refinement Hello, I am trying to run restrained refinement with Refmac5 (version 5.5.0109), including refinement of isotropic temperature factors, and I am seeing some very unusual behavior by the program. In the output pdb file, nearly all of the individual atomic B factors have a value of 2.0! My data is only to 2.9 Angstrom so I've been told to expect much larger atomic B factors. I am using anisotropy-corrected data (I ran my original data through the ellipsoidal truncation anisotropy correction server from UCLA), but when I repeated the run using the original uncorrected mtz file I still saw an average atomic B around 10. I also looked back at the output pdbs from some previous rigid-body refinements (using the same anisotropy-corrected data) and there the B factors are much higher, 50-100. I'm not sure how to prevent Refmac from making this mistake--can anyone offer a suggestion? Thanks, Kyle Kyle T. Dolan Department of Biochemistry and Molecular Biology The University of Chicago [log in to unmask]