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HL coefficients from phenix.refine?
by William Scott 15 Aug '08

15 Aug '08

Is there a simple way to output HL coefficients in refinement, rather than just map coefficients? William G. Scott Contact info: http://chemistry.ucsc.edu/~wgscott/

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Re: [phenixbb] Neutron exchangeable hydrogen/deuterium positions diverge
by Anna S Gardberg 15 Aug '08

15 Aug '08

Hi, Pavel. That's good to know. (Not pressure you, but) any idea roughly when that will be? -Anna On Thu, Aug 14, 2008 at 5:32 PM, Pavel Afonine <PAfonine(a)lbl.gov> wrote: > Hi Anna, > > Are they very different? I can easily change the code so phenix.refine makes > them identical. The question is do we really need it? I'm not arguing but > just asking. > > > A quick sampling of a handful of residues showed that the separation > at SER and THR HG/DG positions ranged from 0.37 to 1.2 Angstroem. It > seems to me that those values are too high and that there does need to > be a way to constrain them to (or at least restrain them toward) zero. > The separation at the amide positions was much less - 0.04-0.06 > Angstroem. > > > OK, I will add an option to do this. It will appear in one of the next > PHENIX releases. > > Please let me know if you have any other questions or problems! > > All the best, > Pavel. > >

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Neutron exchangeable hydrogen/deuterium positions diverge
by Anna S Gardberg 14 Aug '08

14 Aug '08

Hello, PhenixBB. I am doing joint x-ray/neutron refinement of a hydrogenated protein crystal soaked in D2O buffers, and I've run into a problem with refinement. I hope you can help. I used phenix.ready_set to add deuterium atoms to the exchangeable hydrogen positions. I ran a perl script to set the initial occupancies of those to 0.5 H and 0.5 D (they had been output as 1.0). When I ran phenix.refine with riding hydrogen positions or with individual hydrogen positions, the H and D atoms refined to different positions. How can I constrain the H and D positions to be identical? Regards, Anna Gardberg -- Anna Gardberg Research Associate, Postdoctoral Center for Structural Molecular Biology Oak Ridge National Laboratory Bldg. 4500S, M/S 6142 Oak Ridge TN 37831-6142 phone: 865-576-2173

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phenix.twin_map_utils AssertionError
by hari jayaram 14 Aug '08

14 Aug '08

Hi I am trying to run the following command phenix.twin_map_utils data.file=cy_p10_2_28.1_unique1.mtz model.file=cy_p10_2_28.1.pdb obs_labels=F_p10-2,SIGF_p10-2 free_flag=FreeR_flag When I run phenix.twin_map_utils from phenix version 1.3 final or from the newest cci_aps. I get the following AssertionError ( see below). I think my mtz file is kosher because phenix.refine with the twin_law option handles it well and I can refine with a twin law. Is there something wrong in the syntax or the file. I am attaching the log file with the Assertion Error to this email. Thanks for your help Hari Overall and bulk solvent scale paranmeters and twin fraction estimation ======================================================================= Traceback (most recent call last): File "/Users/hari/cci_apps_sources/mmtbx/mmtbx/command_line/twin_map_utils.py", line 7, in <module> twin_map_utils.run(args=sys.argv[1:]) File "/Users/hari/cci_apps_sources/mmtbx/mmtbx/twinning/twin_map_utils.py", line 306, in run out=log) File "/Users/hari/cci_apps_sources/mmtbx/mmtbx/twinning/twin_f_model.py", line 946, in __init__ assert self.f_obs.indices().all_eq( self.free_array.indices() ) AssertionError

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phenix pdp files and coot - FIXED
by nihmmayerm 13 Aug '08

13 Aug '08

Hi, The problem was that coot choked on the TER and BREAK lines in the PDB, once I removed these 0.4.1 reads the phenix PDBs fine. +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ I've just finished refinements with latest version of phenix (/phenix-1.3-final/build/mac-intel-osx/bin/phenix) in which I used riding hydrogens added with reduc (Molprobity) version and TLS - so I have anisou records - and a bunch of acs. When I open files in coot (coot/0.4.1/bin/coot) I see only 1 chain (I have a dimer chain A and B) and no solvent or other heteroatoms. The file displays fine in pymol - but I want to rebuild with coot. Any ideas ? I'm using the SBGrid install of coot, and a local installation of phenix. Thanks - Mark

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phenix pdp files and coot
by nihmayerm 13 Aug '08

13 Aug '08

Hi, I've just finished refinements with latest version of phenix (/phenix-1.3-final/build/mac-intel-osx/bin/phenix) in which I used riding hydrogens added with refine (Molprobity) version and TLS - so I have anisou records - and a bunch of acs. When I open files in coot (coot/0.4.1/bin/coot) I see only 1 chain (I have a dimer chain A and B) and no solvent or other heteroatoms. The file displays fine in pymol - but I want to rebuild with coot. Any ideas ? I'm using the SBGrid install of coot, and a local installation of phenix. Thanks - Mark

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Segmentation fault with twin-law refinement
by hari jayaram 13 Aug '08

13 Aug '08

Hi I have discovered that my data in the P3 spacegroup is potentially twinned. Truncate and phenix.xtriage indicate that the twin fraction is pretty high ( between 0.35 and 0.42). I am still new to twinned data refinement and still dont know which twin law to pick from the three possibilities for P3 that xtriage lists. I am emailing because , Regardless of the twin law I try , phenix.refine crashes with a Segmentation fault on my Mac Pro leopard 10.5.2 running phenix. 1.3b-rc6 The command that ends with a Python crash and segmentation fault is Command used: phenix.refine cy_p10_2_28.1.pdb cy_p10_2_28.1_unique1.mtz simulated_annealing=true model.ncs refinement.main.ncs=true --overwrite refinement.ncs.excessive_distance_limit=None strategy=group_adp+individual_sites twin_law='-h,-k,l' refinement.input.xray_data.labels=F_p10-2,SIGF_p10-2 > phenix_run2_mhmkl_simulanneal.log phenix.xtriage outputs Statistics depending on twin laws ------------------------------------------------------------------ | Operator | type | R obs. | Britton alpha | H alpha | ML alpha | ------------------------------------------------------------------ | -h,-k,l | M | 0.100 | 0.406 | 0.407 | 0.393 | | h,-h-k,-l | M | 0.071 | 0.426 | 0.439 | 0.458 | | -k,-h,-l | M | 0.090 | 0.411 | 0.417 | 0.415 | ------------------------------------------------------------------ Can you tell me if there is something I am doing wrong . Thanks a tonne for your help Hari Jayaram Postdoc , Brandeis University

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phenix.reduce
by Mayer, Mark (NIH/NICHD) [E] 13 Aug '08

13 Aug '08

Hi, Does phenix.reduce correctly handle pdb files with alt confs? I ran reduce on such a file ang got a warning that only A was used, and when i checked output there were no H on AC B residues. I then sent file to Molprobity server, ran reduce, and now there are H on residues for both ACs. I'm doing this so I can refine with riding hydrogens. Thanks MLM

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secondary structure restraints
by Nikos Pinotsis 11 Aug '08

11 Aug '08

Dear all, I am refinining a 3.5 A structure where several of fragments are already determined in higher resolution (similar to the case I found below). In addition a large part of the structure is quite disordered (two out of four chains). I found a reply about a year ago that secondary structure restraints are not implemented in phenix, is there any new developements that can help the refinement in low resolution? (I have already employed NCS other common posibilities). thank you in advance for any help and best regards Nikos >/ On May 4, 2007, at 5:10 PM, Pavel Afonine wrote: />/ />>/ Hi Jianghai, />>/ />>/ I see several possibilities to think about or/and try out: />>/ />>/ 1) Fix the coordinates of atoms in the domains for which the high />>/ resolution structure is available and refine the rest; />>/ 2) Refine the domains for which the high resolution structure is />>/ available as rigid bodies and for the rest refine individual parameters; />>/ 3) There is no specific option in phenix.refine to restrain the />>/ secondary structure elements, however there is a tedious way of doing />>/ this (according to Ralf) by defining custom bonds and angles between />>/ specific atoms forming the secondary structure motifs. Look />>/ "Definition of custom bonds and angles" in the latest CCI Apps />>/ phenix.refine documentation for technical details. />>/ />>/ You can perform "1)" and "2)" in ONE refinement run by combining />>/ several refinement strategies and using specific selections for />>/ refinable parameters. />>/ />>/ Overall, at 3.8A resolution the refinement of individual atomic />>/ parameters (coordinates, B-factors) is questionable. I would consider />>/ to try to refine group parameters for B-factors (trough TLS or/and />>/ group B (like one B per residue)) and try to switch between rigid />>/ body refinement of smaller fragments of your model and refinement />>/ individual positional parameters or mix of individual and rigid body />>/ refinement. />>/ />>/ Also, I will think about making a specific option for automatic />>/ generation of secondary structure restrains. However, given the />>/ amount of work it may require this option will not appear in near future. />>/ />>/ Pavel. />>/ />>/ />>/ Jianghai Zhu wrote: />>>/ Hi all, />>>/ />>>/ I am refining a low resolution structure (~3.8 A). For some of the />>>/ domains in the structure, we already have high resolution />>>/ structures. Despite of some conformational changes in some loops, />>>/ the core structures should be the same. I am wondering if it is />>>/ possible to restrain the secondary structures in phenix.refine. />>>/ />>>/ Thanks. />>>/ />>>/ Jianghai/ -- --------------------------------- Dr. Nikos Pinotsis Section of Structural Biology Institute of Cancer Research Chester Beatty Laboratories 237 Fulham Road London SW3 6JB, UK Tel: +44 20 7153 5453 / 5447 --------------------------------- The Institute of Cancer Research: Royal Cancer Hospital, a charitable Company Limited by Guarantee, Registered in England under Company No. 534147 with its Registered Office at 123 Old Brompton Road, London SW7 3RP. This e-mail message is confidential and for use by the addressee only. If the message is received by anyone other than the addressee, please return the message to the sender by replying to it and then delete the message from your computer and network.

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dihedral error
by Simon Kolstoe 08 Aug '08

08 Aug '08

phenix.refine keeps on stopping with the error: AssertionError: Conflicting dihedral restraints: tor id: var_002 1. definition from: residue: DRG, conformer A 2. definition from: residue: DRG, conformer A atoms: " CB DRG A 500 " " OG1 DRG A 500 " " PAL DRG A 500 " " OAF DRG A 500 " It is for a phospho-threonine residue whose dictionary I made in PRODRG. I've tried all the different charge states of the phosphate however phenix gives the same error every time. Any ideas? Thanks, Simon

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