December 2025 - phenixbb - phenix-online.org

real space refinement of 3Fe4S cluster
by Amy Fernandez 31 Dec '25

31 Dec '25

Hello Phenix BB, I'm attempting to refine a model with a 3Fe4S cluster into a medium resolution cryoEM map. Every time I run a refinement job, the cluster comes out all wonky, as in the attached image. I found one previous thread on this topic and when I played with the "superpose_ideal_ligand" setting, I got an error stating that the F3S residue is missing atoms. Should I just generate a restraint file? Any advice on how others have handled this welcome. Best, Amy __________________________________________________ Amy Fernandez Berger Lab<https://berger.med.jhmi.edu/> - The Johns Hopkins University School of Medicine PhD Candidate - Program for Molecular Biophysics<https://pmb.jhu.edu/>

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transform C2 to P1 and the R-free set
by Jorge Iulek 27 Dec '25

27 Dec '25

Dear all, I got a set of images (very recently) . Dials gives me: +------------+--------------+--------+--------------+----------+-----------+-------------------------------------------+----------+-----------+ | Solution | Metric fit | rmsd | min/max cc | #spots | lattice | unit_cell | volume | cb_op | |------------+--------------+--------+--------------+----------+-----------+-------------------------------------------+----------+-----------| | * 2 | 0.3001 | 0.066 | 0.272/0.272 | 10685 | mC | 212.43 81.92 133.04 90.00 113.12 90.00 | 2129290 | a-2*b,a,c | | * 1 | 0 | 0.052 | -/- | 10559 | aP | 81.95 113.64 133.10 68.50 89.98 69.13 | 1065523 | a,b,c | +------------+--------------+--------+--------------+----------+-----------+-------------------------------------------+----------+-----------+ Many indications are that the 2-fold axis is not really crystallographic, but a pseudo one. My point in this case is that reflections related by this "almost" 2-fold axis should go into the same set, free and work, this in the (new) P1 setting. I could not devise clearly how to get a program to do this automatically (say, flag reflections with this pseudo 2 related for free -set ) . Is there? I understand cb_op is the real space operation, possibly out of a crystallography package I can get that, but easier if there is a crystallographic tool. Any thoughts? Thanks, Jorge (Season's Greetings)

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amberprep problem
by George Phillips 26 Dec '25

26 Dec '25

I am trying to run phenix.AmberPrep in phenix-2.0-5885 and get the flollowing but cannot find a leap.log file to check. Any clues? pdb file attached. Thanks, George georgep@Y56NQ4XRRC 7W26 % phenix.AmberPrep noH.pdb minimise=amber_all ================================================================================ Running pdb4amber on noH.pdb ================================================================================ ================================================== Summary of pdb4amber for: noH.pdb =================================================== ----------Chains The following (original) chains have been found: A B S ---------- Alternate Locations (Original Residues!)) The following residues had alternate locations: None -----------Non-standard-resnames ---------- Missing heavy atom(s) None ================================================================================ Setting up library files for non-standard residues ================================================================================ ================================================================================ Preparing asu files and 4phenix_noH.pdb ================================================================================ Checking output filenames file : noH_asu.prmtop Sorry: Output file not present : noH_asu.prmtop Check contents of “leap.log"

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Phenix real space refine use for Cryo-EM model refinement
by dishajawadekar295＠gmail.com 23 Dec '25

23 Dec '25

Hi, I am using Phenix real space refine to refine my cryo-EM model. My model is looking good (based on molprobity statistics) but I would like to run an additional round of Phenix refinement without allowing the program to move the side chains. From what I see, Phenix moves the side chains by default. What settings can I use to avoid this? Thank you.

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phenix.polder issue
by robert＠oeffner.net 19 Dec '25

19 Dec '25

Hi, I think there's a slight glitch in Polder which I am currently testing. The program works fine. However, the log file shows the full phil parameter for the selection string solvent_exclusion_mask_selection whereas the json file does not. As an example I have a log file: ------------------------------------------------------------------------------- data_manager { miller_array { file = "../74343_262277_1_1.mtz" } default_miller_array = "../74343_262277_1_1.mtz" model { file = "../74343_262277_4_1+ligands.pdb" } default_model = "../74343_262277_4_1+ligands.pdb" } polder { box_buffer = 5 } solvent_exclusion_mask_selection = ( chain Y and ( ( resseq 1 and name C1 \ ) or ( resseq 1 and name C2 ) or ( \ resseq 1 and name C3 ) or ( resseq 1 and \ name C4 ) or ( resseq 1 and name C5 ) or \ ( resseq 1 and name N6 ) or ( resseq 1 \ and name C7 ) or ( resseq 1 and name H8 \ ) or ( resseq 1 and name H9 ) or ( \ resseq 1 and name H10 ) or ( resseq 1 \ and name H11 ) )) mask_output = True output { overwrite = True } But in the polder_modified.eff.json file it reads: ------------------------------------------------------------------------------- { "data-manager-miller-array-file": "../74343_262277_1_1.mtz", "data-manager-default-miller-array": "../74343_262277_1_1.mtz", "data-manager-model-file": "../74343_262277_4_1+ligands.pdb", "data-manager-default-model": "../74343_262277_4_1+ligands.pdb", "polder-box-buffer": 5, "solvent-exclusion-mask-selection": "(", "mask-output": true, "output-overwrite": true } Regards, Rob

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new XDS package (BUILT=20251103) for academic users
by Kay Diederichs 16 Dec '25

16 Dec '25

Dear XDS users, the latest binaries of the XDS package are available for academic users from the “downloading” link at https://xds.mr.mpg.de/ . As the linked “Release Notes” indicate, a few changes were made to output formats, and the requirement for a dynamic library (libquadmath.so), which is not installed by default in most Linux distributions, was eliminated. If you are already running BUILT=20250714, there is no reason to upgrade. In addition to the routine testing against specific datasets performed by Wolfgang Kabsch and me for new XDS packages, this one was tested against a larger database of datasets put together by Clemens Vonrhein and Gerard Bricogne (Global Phasing), who also devised a range of analysis and display tools. A procedure for comparing this and future XDS packages against earlier ones, using a further expanded database, is being implemented in the “XDS reproducibility project” that was convened by Max Burian (Dectris) and is hosted in the Dectris Cloud. Besides the five people mentioned, Camilla Larsen (Dectris), Gleb Bourenkov (EMBL Hamburg) and Ashwin Chari (Max Planck Institute for Multidisciplinary Sciences, Göttingen) are contributing to this project. We expect this effort will ensure the reliability of the XDS package, improve its usage, and enhance the resulting data quality. Best wishes, Kay

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REMINDER – Abstract Submission - 2026 ISMSM || DEADLINE - December 15
by Jose Artur Brito 11 Dec '25

11 Dec '25

Dear Colleagues, This is a reminder that abstract submission for the 7th International Symposium on Microbial Sulfur Metabolism (7th ISMSM), will CLOSE in December 15th. The meeting will take place in Lisbon, Portugal, from 17–20 March, 2026, and will bring together researchers from across the globe to explore the latest advances in microbial sulfur cycling, from molecular mechanisms to ecological, environmental and health perspectives. A number of talks will be selected from the abstracts, so please register and submit your abstract! https://wmsm.itqb.unl.pt/registration/ 👉 For more information visit: https://wmsm.itqb.unl.pt/ Please share this announcement with colleagues and collaborators who may be interested. We look forward to welcoming you in Lisbon next March! The Organising Committee Inês Cardoso Pereira, Filipa Sousa, José Artur Brito, Andreia Pimenta and Américo Duarte ismsm(a)itqb.unl.pt --

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