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Issues with zero B-factor and ADP refinement
by sylee00＠snu.ac.kr 24 Mar '25

24 Mar '25

Dear all, I am encountering issues related to B-factors and ADP refinement in Phenix and would appreciate any insights or suggestions. I am currently working on my first PDB file, but I've noticed that many atoms in the PDB file have a B-factor of 0. As far as I understand, B-factor values are calculated by ADP refinement in Phenix real-space refinement, but even after running real-space refinement (with ADP on in refinement settings), the B-factor remains 0 for many atoms. I am currently using Phenix 1.20 on Windows (Newest version available on window). I also attempted to run Phenix 1.21 on a Linux in other computer, but when ADP refinement is enabled, the process starts normally but halts during the ADP refinement step. So I couldn't test whether the issue is fixed in the newest version. Aside from the B-factor issue, I am also experiencing an inssue related to ADP refinement: When I run real-space refinement with ADP refinement enabled, the process starts normally but halts during the ADP refinement step. According to the log file, other refinement steps proceed without issues, but it fails to progress at the ADP refinement stage. Additionally, when I try to pause the process, I receive a "NoSuchProcess" error, so ADP refinement process may have unexpectedly terminated. At first, I thought it's the issue related to system performance or hardware differences, because adp refinement with this pdb file and identical parameters works on some computer but fails on others (the same version of Phenix). Still it's weird because this issue has occurred unexpectedly, as ADP refinement previously worked in my computer under the same conditions without any problems and also other PDB files run without any problems in my computer. I would appreciate any insights or suggestions on how to resolve this. Thanks

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phenix low resolution refinement strategies
by a131943017＠163.com 21 Mar '25

21 Mar '25

Hi, how do I set the optimization parameters to make free R lower for 3.2Å x-ray crystallography data, or in other words, how do I go about determining whether the optimization strategy is appropriate or not? Questions from a Phenix Beginner.

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seeking help for phenix - coot model building
by tim smith 20 Mar '25

20 Mar '25

Hi everyone, I’m currently working on building a model and have encountered some difficulties with the map-model process. I would greatly appreciate it if anyone could assist me in either helping to build the model or teaching me how to do it. I’m happy to offer a suitable reward for your time and help. Thank you in advance for considering! Regards, Stim

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CSD changes conformation to planar during phenix.refine
by Andrea Smith 20 Mar '25

20 Mar '25

Hi all, I have a structure where I clearly see that one of the cysteines is oxidised. I have modelled CSD instead of CYS and when I do real space refine in Coot, the CSD sits nicely in the density. When I submit the phenix.refine job, I can see that the geometry changes and now the SOOH is planar. I tried to add the CSD.cif from PDB into phenix.refine as restraints, but it doesn't help and during the automatic refinement the geometry is changed to planar again. Anyone experienced same thing? What do I do? Thank you, Andrea

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Trouble with GTP/GDP refinement.
by DIEGO ORTIZ DE ELGUEA LOPEZ DE DICASTILLO 18 Mar '25

18 Mar '25

Dear phenixbb: I'm working with a GTP binding protein and have had some problems running phenix_refine. In my unit cell there are two molecules one with GDP and one with GTP, which I added in Coot(0.9.8). When refining the following error message pops-up : "Fatal problems interpreting model file: Number of atoms with unknown nonbonded energy type symbols:4 Please edit the model file to resolve the problems and/or supply a CIF file with matching restraint definitions, along with apply_cif_modifications and apply_cif_link parameter definitions if necessary". Checking the log file I found that the problem seems to be hydrogen atoms from these ligands Number of atoms with unknown nonbonded energy type symbols: 4 "HETATM 6499 H5' GTP A 501 .*. H " "HETATM 6502 H5'' GTP A 501 .*. H " "HETATM12939 H5' GDP B 501 .*. H " "HETATM12940 H5'' GDP B 501 .*. H " Including the corresponding .CIF files (dowloaded from PDB) did not solve the problem and the same error popped. Since I'm in the initial stages of the refinement I'm running phenix with bindividuals. Could anybody save my day giving me some light into this issue? Cheers, Diego

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.cif file has 'UNK' auth_asym_id
by Kevin M Jude 14 Mar '25

14 Mar '25

I’ve finished refining a structure with three protein chains A, B, C. The pdb file looks ‘normal’ to me, but when I inspect the .cif file written by phenix, the auth_asym_id for chains B and C is ‘UNK’. label_asym_id is correct for all chains. I’m not really sure what the difference is between the auth_ and label_ fields. When I try to perform actions on the .cif file, I get duplicate atom label errors. Here’s a few example lines from the .pdb and .cif files, where auth_asym_id is field 6 and label_asym_id is field 16 ATOM 460 OXT PRO A 59 5.272 55.689 31.481 1.00 52.63 O ANISOU 460 OXT PRO A 59 6541 6212 7244 1448 1260 96 O TER ATOM 461 N ALA B 2 39.292 61.974 39.403 1.00 67.81 N ANISOU 461 N ALA B 2 7118 8729 9916 -1711 -388 2066 N ATOM 460 OXT . PRO A 59 ? 5.27169 55.68852 31.48123 1.000 52.63052 O ? A ? 58 1 ATOM 461 N . ALA UNK 2 ? 39.29207 61.97430 39.40271 1.000 67.80544 N ? B ? 1 1 I’m able to convert the pdb file to a usable cif file using gemmi but wanted to report this weird behavior with phenix 1.21.2_5419. -- Kevin Jude, PhD Structural Biology Research Specialist, Garcia Lab Howard Hughes Medical Institute Stanford University School of Medicine Beckman B177, 279 Campus Drive, Stanford CA 94305

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Pdb validation report via phenix
by Stachowski, Tim 12 Mar '25

12 Mar '25

I’ve always found the phenix.get_pdb_validation tool to be super helpful to gauge where my refinements are relative to the PDB, especially since I work mainly through the command line. But sometime around late last year, the R-free metric stopped being calculated (probably related to “EDS: FAILED”). Is there a way to bring this part of the tool back – or does anyone have a work around they can share? I’m running the command like: phenix.get_pdb_validation_report final-coot-3_refine_001.reflections.cif final-coot-3_refine_001.cif with version: phenix-2.0rc1-5599 Thanks Tim -- Tim Stachowski, PhD St. Jude Children’s Research Hospital ________________________________ Email Disclaimer: www.stjude.org/emaildisclaimer Consultation Disclaimer: www.stjude.org/consultationdisclaimer

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Refining the structure of Ribosome and the system crash
by Rajnandani Kashyap 12 Mar '25

12 Mar '25

Hello Everyone I am trying to run jobs in phenix (real space refinement alignment with the other modelling jobs), but the system always crashes, and refinement doesn't complete. This is the structure of ribosome, and I am wondering what to do to get through the refinement. Is there any specific parameters I should be using. I tried to change the processors to 15 for a 20-processor computer. Let me know. Thanks in advance. FYI: There is no error message in the log. Best, Rajnandani ---------------------------------------------------------------------- Rajnandani Kashyap, Ph.D. Postdoctoral Fellow Department of Biochemistry and Molecular Biology Saint Louis University, Antony Lab 1205 Carr Lane, DRC 451 St. Louis, MO 63104 https://orcid.org/0000-0002-9141-1168 -----------------------------------------------------------------------

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Ion placement (anomalous) + occupancy refinement
by miha.pavsic＠fkkt.uni-lj.si 07 Mar '25

07 Mar '25

Hi everyone, I have a dataset from a protein that contains 2 Ca2+ binding sites. The Ca2+ loaded protein was crystallized in the presence of Tb3+ which at one site mostly replaced Ca2+, however at the other site the Tb3+/Ca2+ ratio appears to be much lower (judging from anomalous map; data collected at 1.3 Å wavelength, MR for phasing). The occupancy sum of Tb3+ and Ca2+ at each of the two sites is strongly believed to be 1. While I am aware of the ion placement option in phenix.refine, I am not so sure how to refine the partial occupancies using anomalous data, if possible. Many thanks for any hints, Miha

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AKM in Phenix
by lucas.santosouza＠outlook.com 07 Mar '25

07 Mar '25

Hi everyone, Is there still support for the generation of Average Kick Maps in Phenix? I am using both versions 1.21.2-5419 and the nightly build 2.0rc1-5555. I added kicked=True to the maps.params, but phenix.maps gives me "Unused parameter definitions: maps.map_coefficients.kicked (file "maps.params", line 53)". I also cannot see the "Kicked map" check box in the Create Maps GUI. Cheers, Lucas

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