- phenixbb - phenix-online.org

picking Rfree set
by David Garboczi 23 Jan '08

23 Jan '08

Does phenix.refine take NCS into account when picking the Rfree set? Thin shells, or other strategy... Dave --

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Re: [phenixbb] autosol : input_ncs_file
by Tom Terwilliger 23 Jan '08

23 Jan '08

Hi Bryan, No, autosol does not let you tell it what the NCS is with input_ncs_file. This is a good idea, however... -Tom T At 06:45 PM 1/15/2008, you wrote: >using PHENIX VERSION: 1.3b of 20-11-2007. > >does phenix.autosol use "input_ncs_file"? > >the documentation implies that phenix.autosol will take `input_ncs_file` >(at the 'find_ncs' entry, "input_ncs_file" is mentioned but no where >else), yet, i get a 'Sorry, unknown file or keyword:' message with no such >command line option listed. > >-bryan >_______________________________________________ >phenixbb mailing list >phenixbb(a)phenix-online.org >http://www.phenix-online.org/mailman/listinfo/phenixbb Thomas C. Terwilliger Mail Stop M888 Los Alamos National Laboratory Los Alamos, NM 87545 Tel: 505-667-0072 email: terwilliger(a)LANL.gov Fax: 505-665-3024 SOLVE web site: http://solve.lanl.gov PHENIX web site: http:www.phenix-online.org ISFI Integrated Center for Structure and Function Innovation web site: http://techcenter.mbi.ucla.edu TB Structural Genomics Consortium web site: http://www.doe-mbi.ucla.edu/TB

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modify_start_model.adp.set_b_iso doesn't seem to work on PDB files with ANISOU cards
by Stephen Graham 22 Jan '08

22 Jan '08

Hi all, I just tried to reset my B values to the wilson B before TLS refinement (in an attampt to shake some model bias that I am sure is hiding somewhere in my temperature factors...). My start model was a TLS-refined PDB file from phenix.refine (hence with ANISOU cards). I issued the following command: > phenix.refine my_model.pdb my_data.mtz modify_start_model.adp.set_b_iso=60 output.prefix=my_model_resetB main.number_of_macro_cycles=0 As far as I can tell, this should reset my B values to 60 and then exit. However, when I look at the resultant PDB file the Bs for all the solvent molecules 60 but for the protein they are not; rather the protein Bs are almost identical to the starting PDB file. If I try to remove the TLS-derived ANISOU cards by adding the command line option "adp.convert_to_isotropic=true" the result is the same (except the output PDB file no longer has ANISOU cards). However, if I strip out the ANISOU cards from my starting pdb file and _then_ run the above command the resultant PDB file _does_ have the correct values for both protein and solvent. It seems like modify_start_model.adp.set_b_iso=60 does not work when atom has an ANISOU card. The behaviour I would *expect* would be for the adp be reset to an 'isotropic' 60 (i.e. set the diagonal elements to 1 and the off-diagonals to 0). Is this a bug, or am I doing something silly? Cheers, Stephen -- Dr Stephen Graham Nuffield Medical Fellow Division of Structural Biology Wellcome Trust Centre for Human Genetics Roosevelt Drive Oxford OX3 7BN United Kingdom Phone: +44 1865 287 549

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d_min_textal=
by Bryan W. Lepore 19 Jan '08

19 Jan '08

the documentation says : "Textal has an optimal high-resolution limit of 2.8 A" is that to say that resolutions != 2.8 are not optimal? -bryan

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Re: [phenixbb] disulfide bonds in phenix.refine
by Ralf W. Grosse-Kunstleve 19 Jan '08

19 Jan '08

Hi Allister, > 1) How do I specifically prevent a disulfide bond from being defined > between two sulfurs that are close together (I tried manipulating the > "disulfide_distance_cutoff" variable but this doesn't seem to stop a > disulfide being formed). If you set, e.g. disulfide_distance_cutoff=0.1 you shouldn't get any disulfide bonds anymore. I just tried it on a small structure and it worked as expected. > 2) How can I soften the restraint on the disulfide bond length for > specific cysteine residues. With the current phenix.refine you cannot edit the automatically determined disulfide bonds (sorry). However, you can use disulfide_distance_cutoff=0.1 to turn off the automatic bonds. Then use geometry_restraints.edits (see documentation at http://phenix-online.org/documentation/refinement.htm) to define the disulfides manually one by one, with the ideal distances and sigmas you want to use. Use a log file from a previous phenix.refine run to obtain the list of all disulfides. Ralf

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disulfide bonds in phenix.refine
by Allister.Crow＠uea.ac.uk 19 Jan '08

19 Jan '08

Hello all, I am currently trying to refine a structure (with phenix.refine) that contains a number of disulfide bonds. Many of these disulfides appear to be partly broken such that the default restraints given to these disulfides by phenix.refine cause the cysteine sulfur atoms to be placed too close to one another. This results in difference density in the fo-fc map. I want to try to model these partially broken states a bit more accurately, either by modelling two alternative conformations (i.e. one cysteine pair in a disulfide and the other pair as free thiols) or by allowing the disulfide bond distance to stretch. Currently refinement drives the S-S bond length close to dictionary values regardless of how far apart I model the cysteines in my input pdb file and whether the density implies a bridge or not. My two questions are: 1) How do I specifically prevent a disulfide bond from being defined between two sulfurs that are close together (I tried manipulating the "disulfide_distance_cutoff" variable but this doesn't seem to stop a disulfide being formed). 2) How can I soften the restraint on the disulfide bond length for specific cysteine residues. Thanks for your time. Dr. Allister Crow

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Continue from an AutoBuild job abruptly killed
by Miguel Ortiz-Lombardía 18 Jan '08

18 Jan '08

Dear all, We had a problem with a machine running AutoBuild, which resulting in the computer going down and the AutoBuild job consequently killed. I've tried to find out if there is a way to continue the job (it had been running for four days and still had a few hours to go I guess: a pretty big unit cell) but I failed. I would appreciate if someone could point to the relevant pages in the manual/tutorials or give me advice about how to do such a thing. If that's possible, of course. We're using the latest phenix (1.3b-rc6) and cci apps. Thank you! Miguel -- http://www.pangea.org/mol/spip.php?rubrique2 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Je suis de la mauvaise herbe, Braves gens, braves gens, Je pousse en liberté Dans les jardins mal fréquentés! Georges Brassens

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MSE gap
by Troy E Messick 17 Jan '08

17 Jan '08

Hello, I seem to be having a problem with phenix.refine and the seleno-methionine residue (resname MSE). It seems that I have a gap in the peptide bond between the C atoms and the N atom of the subsequent residue. Is there something I could add to the restraints_edits.params file to get it to click together? What is the distance_ideal and sigma for a peptide bond? Thanks for your help, Troy

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phenix.find_ncs and DANO
by Bryan W. Lepore 16 Jan '08

16 Jan '08

in principle, phenix.find_ncs should be fine with FP=DANO, right? and - do i understand correctly that phenix only correlates the map with the .pdb sites, and does not rotate the map about itself (like in getax, i think)? -bryan p.s: i can run phenix.find_ncs with FP=DANO, but seems that resolve wants it to be FP as usual.

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autosol : input_ncs_file
by Bryan W. Lepore 16 Jan '08

16 Jan '08

using PHENIX VERSION: 1.3b of 20-11-2007. does phenix.autosol use "input_ncs_file"? the documentation implies that phenix.autosol will take `input_ncs_file` (at the 'find_ncs' entry, "input_ncs_file" is mentioned but no where else), yet, i get a 'Sorry, unknown file or keyword:' message with no such command line option listed. -bryan

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