July 2009 - phenixbb - phenix-online.org

sigma cutoff
by dziuba＠amu.edu.pl 24 Jul '09

24 Jul '09

Hi, According to the Phenix manual, phenix.refine uses no sigma cutoff by default. Since I haven't changed this manually, why do I see in my pdb file MIN(FOBS/SIGMA_FOBS) 1.340? Thanks for help, Karolina

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ENSEmble parameters when the model is an EM map
by Peter Grey 24 Jul '09

24 Jul '09

Dear benevolent experts, I am trying to use Phaser for molecular replacement with EM-map as a model. The EM map, originally in a small P1 cell, was put in large P1 using CCP4's MAPROT and a mask that was defined by a certain cut-off level. Could you please advise me how to derive the EXTEnt and CENTre parameters needed for ENSEmble building ? Does the simple way of giving the size of the original P1 as the EXTEnt and its centre as CENTre sound reasonable ? I would be grateful for any advice and comments, Peter.

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anisotropic ADP factor refinement and optimize_wxc
by Joyce, Gordon M. (NIH/NIAID) [F] 22 Jul '09

22 Jul '09

Dear All, I have just recently started using phenix.refine and I hope I can get some advice. I am trying to refine my structure with anisotropic ADP factors while also optimizing the weighting parameters.When I give the following command, anisotropic refinement is carried out but optimization is not carried out as far as I can see (ie the rms bond and angles are not reduced, which is one of my concerns at the moment). phenix.refine protein1.pdb 072109checks.mtz ordered_solvent=true strategy=individual_adp adp.individual.anisotropic="not element H" optimize_wxc=true --overwrite pdb output values REMARK Start: r_work = 0.1952 r_free = 0.2388 bonds = 0.015 angles = 1.646 REMARK Final: r_work = 0.1413 r_free = 0.2448 bonds = 0.015 angles = 1.646 If I give the following command, optimization occurs and rms bond and angle values decrease. phenix.refine protein1.pdb 072109checks.mtz optimize_wxc=true --overwrite REMARK Start: r_work = 0.2048 r_free = 0.2388 bonds = 0.015 angles = 1.646 REMARK Final: r_work = 0.1917 r_free = 0.2352 bonds = 0.009 angles = 1.301 Is it possible to refine both anisotropic B factors and optimize ADP factors in the same run. Any advice would be great. Thanks, Gordon

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Phenix.refine coordinate error estimate discrepancies
by Phil Jeffrey 21 Jul '09

21 Jul '09

There seems to be a large discrepancy between the likelihood-based coordinate error estimate depending on whether the intensities or structure factor magnitudes are used, which doesn't make any sense to me. If I do: % phenix.refine rebuild.pdb data_withI.mtz phenix.refine picks up Imean and SigImean from the MTZ and refines the structure xray_data { file_name = "data_withI.mtz" labels = "IMEAN,SIGIMEAN" r_free_flags { file_name = "data_withI.mtz" label = "FreeR_flag" test_flag_value = 0 } then I get: | maximum likelihood estimate for coordinate error: 1.39 A But if I create an MTZ file without the intensities by using CAD on the original file, and use the same coordinate file: % phenix.refine rebuild.pdb data_withoutI.mtz phenix.refine picks up the structure factors instead: xray_data { file_name = "data_withoutI.mtz" labels = "F,SIGF" r_free_flags { file_name = "data_withoutI.mtz" label = "FreeR_flag" test_flag_value = 0 } } then this seems to be the right ballpark for a 1.75 Angstrom structure.... | maximum likelihood estimate for coordinate error: 0.28 A Similar R-factors, but there is a factor of 10 difference in the scale reported here: I's: r_work= 0.2266 r_free= 0.2570 ksol= 0.41 Bsol= 50.00 scale= 0.097 F's: r_work= 0.2221 r_free= 0.2557 ksol= 0.41 Bsol= 50.00 scale= 0.965 Version: 1.4 Release tag: 3 cctbx tag: 2008_12_07_1353 Platform: mac-intel-osx osx-10.5.6 User: phil Cheers, Phil Jeffrey Princeton

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Assertion Error when using kicked maps in solvent update
by Schubert, Carsten [PRDUS] 21 Jul '09

21 Jul '09

Hi In 1.4.106 I get the following Assertion Error when I use kicked maps (refinement.ordered_solvent.use_kick_maps=True) in the solvent update section: Traceback (most recent call last): File "/raidnet/xdata1/programs/phenix-1.4-106/phenix/phenix/command_line/refi ne.py", line 19, in <module> command_line.run(command_name="phenix.refine", args=sys.argv[1:]) File "/raidnet/xdata1/programs/phenix-1.4-106/phenix/phenix/refinement/comman d_line.py", line 89, in run call_back_handler=call_back_handler) File "/raidnet/xdata1/programs/phenix-1.4-106/phenix/phenix/refinement/driver .py", line 1125, in run call_back_handler = call_back_handler) File "/raidnet/xdata1/programs/phenix-1.4-106/phenix/phenix/refinement/strate gies.py", line 358, in refinement_machine log = log) File "/raidnet/xdata1/programs/phenix-1.4-106/cctbx_project/mmtbx/solvent/ord ered_solvent.py", line 205, in __init__ use_kick_map = self.params.use_kick_maps).peaks_mapped() File "/raidnet/xdata1/programs/phenix-1.4-106/cctbx_project/mmtbx/solvent/ord ered_solvent.py", line 394, in find_peaks log = self.log) File "/raidnet/xdata1/programs/phenix-1.4-106/cctbx_project/mmtbx/find_peaks. py", line 98, in __init__ crystal_gridding_tags = fft_map.tags() File "/raidnet/xdata1/programs/phenix-1.4-106/cctbx_project/cctbx/maptbx/__in it__.py", line 152, in tags return crystal_gridding_tags(self) File "/raidnet/xdata1/programs/phenix-1.4-106/cctbx_project/cctbx/maptbx/__in it__.py", line 158, in __init__ assert gridding.symmetry_flags() is not None AssertionError Running from the same .def file w/o kicked maps works fine. Let me know if you need more info to debug this. Cheers, Carsten

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Duration of a phenix.elbow run
by Dirk 21 Jul '09

21 Jul '09

Hi, I'm trying to create restraints for a carbohydrate ligand using phenix.elbow. If I run it without the --opt command everything works fine, but I'm not completely happy with the geometry of my ligand after refinement. I tried to get an optimized cif by using --opt command, but the program just runs up to the following output: MoleculeClass : H:38 C:23 N: 1 O:19 (PDB format) 81 atoms 83 bonds 151 angles 238 dihedrals -------------------- Time Energy delta E RMS Max Step size and then nothing happens for several hours. Does the optimization needs such a long time and if I let it run overnight (or perhaps longer) I will get an output or is something going wrong? The input is a pdb (I tested several) and I tried both the stable phenix release (1.3) and the current version (1.4). Any help would be very appreciated Thanks Dirk

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Unable to produce kicked maps
by Schubert, Carsten [PRDUS] 17 Jul '09

17 Jul '09

Hi , I am trying to make some kicked maps in 1.4.106. At the end of the run all I am getting is Sorry: Duplicate mtz_label_amplitude FOFCWT Any workaround, except not to use kicked maps? Here the diff_params output for easer debugging. Cheers Carsten <<diff.def>>

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autosol
by sbiswas2＠ncsu.edu 16 Jul '09

16 Jul '09

Hi, I was trying to run autosol using gui however it crashed with the following message: Floating-point error (Python and libc call stacks above) This crash may be due to a problem in any imported Python module, including modules which are not part of the cctbx project. To disable the traps leading to this message, define these environment variables (e.g. assign the value 1): BOOST_ADAPTBX_FPE_DEFAULT BOOST_ADAPTBX_SIGNALS_DEFAULT Is this again a version problem? I am running version 1.4-6 Any help will be appreciated, Shya

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rigid body refinement in phenix.refine
by Pavel Afonine 16 Jul '09

16 Jul '09

To PHENIX users who asked about this: I recall several people (unfortunately, I don't remember who exactly) asked me about the details of rigid-body refinement implementation in phenix.refine (MZ protocol) and I promised to let them know when the corresponding paper is published. So here it is: J. Appl. Cryst. (2009). 42, 607-615 Automatic multiple-zone rigid-body refinement with a large convergence radius P. V. Afonine, R. W. Grosse-Kunstleve, A. Urzhumtsev and P. D. Adams http://journals.iucr.org/j/issues/2009/04/00/dd5048/index.html Pavel.

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error message
by zachcp 15 Jul '09

15 Jul '09

A Python error was detected. This is almost certainly a bug; please send an email containing this message to phenixbb(a)phenix-online.org so we can fix it. Thanks! SorryException : No array of observed xray data found. Traceback: Traceback (most recent call last): File "/usr/local/phenix-1.4-3/phenix/wxGUI2/Xtriage.py", line 158, in OnExcept raise event.data SorryException: No array of observed xray data found.

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