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Update waters and chain ID
by Scott Lovell 19 Jun '14

19 Jun '14

Hi All, I'm refining a structure (dev-1726) that contains 24 protein subunits which are assigned to chains A-X in the PDB file. Chains Y and Z are assigned to a couple of ligands and the ordered solvent molecules are chain w (lower case). I decided to give the "Update waters" option a try during refinement but it seems that the chain ID of the ordered solvent is changed to chain S by default. Since I already have a protein subunit assigned to chain S, the following error is obtained when I try to open the model in Coot (ERROR 39 READ: Duplicate sequence number and insertion code.). To enable visualization of the model in Coot, I can of course manually change the chain ID for the ordered solvent in the output PDB file using a text editor. However, is there a way to override the ordered solvent default chain ID in Phenix to prevent duplication? Thanks, Scott __________________________________ Scott Lovell Ph.D., Director Protein Structure Laboratory University of Kansas Del Shankel Structural Biology Center

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More problems with HEM.cif?
by Yarrow Madrona 19 Jun '14

19 Jun '14

Hello, The HEM.cif in $Phenix/chem_data/mon_lib has ideal angles of 1.337 for single bonds on the vinyl groups. HEM CAC CBC coval 1.337 0.02 HEM CAB CBB coval 1.337 0.02 As far as I know these are single bonds and the ideal bond angles should be around 1.5. -Yarrow

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Rigid ligand placement into density map
by Phan, Jason 19 Jun '14

19 Jun '14

Hi All, Is there an option or flag in Phenix LigandFit to place the ligand rigidly with pre-generated conformations without torsional adjustments? Would setting "conformers = 1" and "refine_ligand = false" work? Coot Find Ligand with the "flexible" option unchecked seems to work but it won't tell you which original conformer (SD file) the "fitted ligand" comes from since all the conformers have the same residue name and number. Coot doesn't write out SD format either so any ID associated with the original conformer is lost. Jason

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molprobity coot TODO python script
by wtempel 19 Jun '14

19 Jun '14

Hello, I noticed the following when loading a phenix-created python TODO script using the 4730 and 5100 Linux-x86_64-ubuntu-12.04.3-python-gtk2 coot builds. A "MolProbity to-do list" window opens. GUI functions such as "Show Probe dots" and "Overlap only" are working as expected. Clicking anywhere within the "C-beta outliers" or "Severe clashes" areas of the window moves the display center to problem areas of the structure. But: no text is visible in any of the columns ("Chain", "Residue", "Name", etc. of the "C-beta outliers area"; "Atom 1", Atom 2", "Overlap" of the "Severe clashes"). As a result, I cannot select a specific problem spot for centering. Any ideas? Another molprobity related question: us there a phenix script that produces a list of NQH flip candidates? Thank you, Wolfram Tempel Attached image: Clicking in the white areas on the window in the attached screen grab will move the center of the coot display, but labels for the problem areas are not shown in the window's columns.

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GUI program to calculate effective resolution of a data set
by Alexandre OURJOUMTSEV 19 Jun '14

19 Jun '14

Dear All, Recently, there was a ccp4bb conversation concerning the definition of a ‘real’ (effective) resolution of (incomplete) diffraction data sets. I am happy to announce that a corresponding GUI program EFRESOL is available now and you may download it from the Web site: http://www-ibmc.u-strasbg.fr/arn/Site_UPR9002/efresol/Efresol.html http://www-ibmc.u-strasbg.fr/arn/Site_UPR9002/Sites.html The method is described in L.Urzhumtseva, B.P.Klaholz, A.Urzhumtsev (2013) Acta Cryst., D69, 1921-1934. We would like to thank Joel Bard, Tom Peat, Rajan Prabu and especially Boaz Shaanan for testing the original version of the program. With best wishes, Sacha Urzhumtsev

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Re: [phenixbb] special positions
by Yarrow Madrona 18 Jun '14

18 Jun '14

Hi Pavel, It turns out I do have some special positions. Waters sit near a 2 fold axis. I have given them 0.5 occupancy. No error comes up but they simply get kicked out of the electron density. Maybe I should turn off rigid body refinement since I don't need it? Below is a link to a screen shot. https://www.dropbox.com/s/lt3hqzjmygin9l8/special_position.png On Wed, Jun 18, 2014 at 8:49 AM, Pavel Afonine <pafonine(a)lbl.gov> wrote: > Hi Yarrow, > > oh good! I'm glad you solved the problem -:) > > All the best, > Pavel > > > On 6/18/14, 8:02 AM, Yarrow Madrona wrote: > > Hi Pavel, > > Thanks for your quick response. It turns out that after I reprocessed a > data set in a higher symetry space group I forgot to use a reference mtz so > the orientation was completely off. I just re-ran phaser and everything > worked fine. I didn't run rigid body refinement after phaser. > > The original error message didn't list the atoms and I am not sure how > it could have any atoms on special positions with the solution being > completely wrong. Probably nothing to worry about. > > -Yarrow > > On Tuesday, June 17, 2014, Pavel Afonine <pafonine(a)lbl.gov> wrote: > >> Hi Yarrow, >> >> ok, I wish that error message (that I put a while ago, in 2009 to be >> precise) lists those atoms... Can you send me the file so I can tell you >> what these atoms are? >> >> In general, if at rigid-body refinement stage you have atoms at special >> positions it is unlikely to be right. >> >> Pavel >> >> On 6/17/14, 12:56 PM, Yarrow Madrona wrote: >> >>> Hi, >>> >>> I am trying to do rigid body refinement, however I get an error in >>> phenix telling me that there are atoms at special positions. >>> >>> I am not sure how to determine which atoms are at special positions so >>> that I can exclude them from rigid body refinement. Can someone help me >>> with this? Thank you. >>> >>> -Yarrow >>> >> >> >

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Calculate F (model) + Calculate Map Correlation
by George Devaniranjan 18 Jun '14

18 Jun '14

Hi, I am trying to use phenix and I was trying to do the following: Take a PDB, generate a MTZ file using Calculate F (model) and lets call it native.mtz then change a few phi and psi values of the pdb (so its slightly different from the native), run Calculate F (model) model.mtz Now I tried to calculate the CC of the two MTZ using Calculate Map Correlation. I get the following: "Missing at least one map file or label" What am I doing wrong? Thank you, George

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Calculation of RSR for a fragment of PDB
by George Devaniranjan 18 Jun '14

18 Jun '14

Hi everyone, I apologize at the beginning itself as I am new to using PHENIX/X-ray crystallography so this question might not make the most sense but I will try and explain it well. I cut out a part of a map for a PDB fragment using phenix map cut out density resulting in a MTZ file. Now I changed the fragment (changed its phi and psi externally) and want to calculate the RSR [real-space R -factor] for the model based on the old density (to check if I have made things worse or not). how can I go about this? I tried using phenix.refine couldn't get it to work. I have attached the MTZ fragment, the original PDB fragment and the modified PDB fragment. native: nativeFragment.pdb model: modelledFragment.pdb MTZ: cut_out_density.MTZ (I can see mine is worse but I want to quantify that "badness") Thank you, George

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Re: [phenixbb] special positions
by Yarrow Madrona 18 Jun '14

18 Jun '14

Hi Pavel, It turns out I do have some special positions. Waters sit near a 2 fold axis. I have given them 0.5 occupancy. No error comes up but they simply get kicked out of the electron density. Maybe I should turn off rigid body refinement since I don't need it? Below is a link to a screen shot. https://www.dropbox.com/s/lt3hqzjmygin9l8/special_position.png -Yarrow On Wed, Jun 18, 2014 at 8:49 AM, Pavel Afonine <pafonine(a)lbl.gov> wrote: > Hi Yarrow, > > oh good! I'm glad you solved the problem -:) > > All the best, > Pavel > > > On 6/18/14, 8:02 AM, Yarrow Madrona wrote: > > Hi Pavel, > > Thanks for your quick response. It turns out that after I reprocessed a > data set in a higher symetry space group I forgot to use a reference mtz so > the orientation was completely off. I just re-ran phaser and everything > worked fine. I didn't run rigid body refinement after phaser. > > The original error message didn't list the atoms and I am not sure how > it could have any atoms on special positions with the solution being > completely wrong. Probably nothing to worry about. > > -Yarrow > > On Tuesday, June 17, 2014, Pavel Afonine <pafonine(a)lbl.gov> wrote: > >> Hi Yarrow, >> >> ok, I wish that error message (that I put a while ago, in 2009 to be >> precise) lists those atoms... Can you send me the file so I can tell you >> what these atoms are? >> >> In general, if at rigid-body refinement stage you have atoms at special >> positions it is unlikely to be right. >> >> Pavel >> >> On 6/17/14, 12:56 PM, Yarrow Madrona wrote: >> >>> Hi, >>> >>> I am trying to do rigid body refinement, however I get an error in >>> phenix telling me that there are atoms at special positions. >>> >>> I am not sure how to determine which atoms are at special positions so >>> that I can exclude them from rigid body refinement. Can someone help me >>> with this? Thank you. >>> >>> -Yarrow >>> >> >> >

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(no subject)
by Orpheus Mandal 18 Jun '14

18 Jun '14

Hi, Is there any way to perform unrestrained refinement on some selected residues in phenix GUI? Thanks, Orpheus

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